Opinion for the court filed by Senior Circuit Judge RANDOLPH.
Opinion concurring in part and dissenting in part filed by Circuit Judge BROWN.
RANDOLPH, Senior Circuit Judge:I.
This appeal has its genesis in 26 U.S.C. § 4251, which imposes an excise tax “on amounts paid for ... toll telephone service.” Telephone service is taxed only if its price “varies in amount with the distance and elapsed transmission time of each individual communication.” Id. § 4252(b). Technological advances of the last few decades changed cost structures and, as a result, telephone companies began charging only by elapsed transmission time. The Internal Revenue Service, however, continued to collect the tax.
Beginning in 2005, the Service lost a series of cases challenging the tax. Five courts of appeals, including this court, held that § 4251 did not permit the Service to tax telephone service with distance-invariant pricing.1 Around that time, the three plaintiffs in this consolidated appeal (Cohen, Sloan, and Gurrola) filed separate putative class-action suits challenging the tax. Initially, plaintiffs raised a variety of constitutional and statutory claims, seeking refunds and other relief. In re Long-Distance Tel. Serv. Fed. Excise Tax Refund Litig. (Long Distance Tel. I), 539 F.Supp.2d 281, 288-89 (D.D.C.2008). The Judicial Panel on Multidistrict Litigation consolidated the suits in the District Court for the District of Columbia. In re Long-Distance Tel. Serv. Fed. Excise Tax Refund Litig., 469 F.Supp.2d 1348 (J.P.M.L. 2006).
After two of the three plaintiffs — Cohen and Sloan — filed their complaints, the Service issued without notice and comment Notice 2006-50, 2006-1 C.B. 1141 (May 26, 2006). Citing the losses in the courts of appeals, the Notice declared that the Service would no longer tax telephone service priced without regard to distance, id. §§ 1(a), 4(c), and established a procedure to refund illegally collected excise taxes, id. § 5. Taxpayers could “request a credit or refund ... on their 2006 Federal income tax returns.” Id. § 5(a)(2). The Notice allowed taxpayers to claim as a refund either the amount of taxes actually *458overpaid or a safe harbor amount for which no documentation was required. Id. § 5(c).
Cohen and Sloan amended their complaints to add claims relating to Notice 2006-50 under the Administrative Procedure Act (APA), 5 U.S.C. §§ 701 et seq. See Long Distance Tel. I, 539 F.Supp.2d at 288-89. Sloan squarely raised both substantive and procedural challenges, while Cohen made only a substantive APA argument. Id. The district court dismissed all three complaints. Id. at 287. Regarding the APA claims, the district court held that Notice 2006-50 was not judicially renewable because it was “a statement of internal IRS policy without the force and effect of law.” Id. at 307; see id. at 306-11.
Plaintiffs appealed the dismissal of their APA claims, and a panel of this court reversed,2 concluding that Notice 2006-50 “operates as a substantive rule that binds the IRS, excise tax collectors, and taxpayers.” Cohen v. United States (Cohen I), 578 F.3d 1, 6 (D.C.Cir.2009). The court also rejected the Service’s arguments that the Declaratory Judgment Act, 28 U.S.C. § 2201, and the Tax Anti-Injunction Act, 26 U.S.C. § 7421, deprived it of jurisdiction. 578 F.3d at 12-14. Judge Kavanaugh dissented from the panel opinion. He argued that plaintiffs’ APA claims were barred by the Declaratory Judgment Act, which prohibits suits seeking declaratory relief “with respect to Federal taxes.” See id. at 17-20.
The full court granted the Service’s petition for rehearing en banc to consider whether the Tax Anti-Injunction Act or the Declaratory Judgment Act barred the court from hearing plaintiffs’ suits. Cohen v. United States, 599 F.3d 652 (D.C.Cir. 2010)(en banc) (per curiam). The court determined that plaintiffs’ APA claims could proceed. Cohen v. United States (Cohen II), 650 F.3d 717, 736 (D.C.Cir. 2011). Adopting much of the Cohen I panel’s reasoning, the en banc majority ordered “the district court [to] consider the merits of [plaintiffs’] APA claim on remand.” Id. Judge Kavanaugh, joined by Chief Judge Sentelle and Judge Henderson, dissented, arguing that an APA suit was unavailable because tax refund suits afforded plaintiffs an adequate legal remedy. Id. at 738^42.
On remand, the district court held that Notice 2006-50 was promulgated without notice and comment in violation of the APA. In re Long-Distance Tel. Serv. Fed. Excise Tax Refund Litig. (Long Distance Tel. II), 853 F.Supp.2d 138, 142-43 (D.D.C. 2012). Having found a violation of the APA, the district court prospectively vacated the Notice and remanded to the Service. Id. at 146. The court declined to set a timetable for any further action by the Service because no “law unequivocally requires such action.” Id.
Plaintiffs then moved for entry of final judgment and an interim award of attorney’s fees under the Equal Access to Justice Act, 28 U.S.C. § 2412(b) & (d). The district court entered final judgment in favor of plaintiff Sloan only on her procedural APA claim. It entered judgment in favor of the government against both Cohen, who raised only substantive APA challenges that the court did not need to address, and Gurrola, who failed to raise any APA arguments. In re Long-Distance Tel. Serv. Fed. Excise Tax Refund Litig. (Long Distance Tel. III), 901 F.Supp.2d 1, 5-7 (D.D.C.2012). The district court denied plaintiffs’ motion for at*459torney’s fees. It first found that plaintiffs could not recover fees under a “common benefit” theory because the litigation’s costs could not be shifted to its large, diffieult-to-ascertain class of beneficiaries with any exactitude. Id. at 8-10. The court rejected plaintiffs’ alternative argument for fees under 28 U.S.C. § 2412(d) because it found the government’s position was “substantially justified.” Id. at 11-12. Plaintiffs have appealed from the court’s refusal to direct the Service on remand to issue a refund rule and from its denial of their interim request for fees.
II.
The government argues that we have no jurisdiction to hear plaintiffs’ appeal because district court orders remanding to agencies are not final appealable decisions. See 28 U.S.C. § 1291; Sierra Club v. USDA, 716 F.3d 653, 656-57 (D.C.Cir. 2013).3 Typically, that is true. A remand order usually allows the agency to correct mistakes in earlier proceedings. Delaying review prevents duplicative appeals from both a district court’s remand order and an agency’s later action. See In re St. Charles Pres. Investors, Ltd., 916 F.2d 727, 729 (D.C.Cir.1990) (per curiam).
But the rule is not absolute. The government may appeal these sorts of remand orders because, unlike most private parties, the government may wind up with “no opportunity to appeal” later, after it has conducted proceedings in compliance with the remand order. Occidental Petroleum Corp. v. SEC, 873 F.2d 325, 330 (D.C.Cir. 1989); see Sierra Club, 716 F.3d at 657. Plaintiffs here face a similar predicament. The Service has not taken any reviewable action in the two years since the district court’s remand order. Indeed the Service has no reason to act. The three-year statute of limitations for filing refund claims, 26 U.S.C. § 6511(a), has likely expired for most potential claimants and there is no need to streamline the refund process for hundreds of millions of taxpayers as there was when Notice 2006-50 issued eight years ago. We find it particularly important that at oral argument government counsel conceded that the Service is “not planning” to engage in future rulemaking on the subject. Oral Arg. Tr. at 23:16. In these unusual circumstances, treating the district court’s remand order as unappealable would “effectively preclude[]” plaintiffs from ever challenging the district court’s decisions. Sierra Club, 716 F.3d at 658; see Ringsby Truck Lines, Inc. v. United States, 490 F.2d 620 (10th Cir. 1974).
We may, in any case, bypass complex questions dealing with appellate jurisdiction when addressing the merits would not require us to “reach[ ] a question of law that otherwise would have gone unaddressed.” See Sherrod v. Breitbart, 720 F.3d 932, 936-37 (D.C.Cir.2013) (quoting Steel Co. v. Citizens for a Better Env’t, 523 U.S. 83, 98, 118 S.Ct. 1003, 140 L.Ed.2d 210 (1988)). The law governing plaintiffs’ challenges is well-established and renders the merits “plainly insubstantial.” Id. (quoting Norton v. Mathews, 427 U.S. 524, 530, 96 S.Ct. 2771, 49 L.Ed.2d 672 (1976)). In such a case we may proceed to decide the merits.
The Supreme Court has endorsed this “practical” approach to finality, particularly in the “twilight zone” where “it is impossible to devise a formula to resolve all marginal eases.” Gillespie v. U.S. Steel Corp., 379 U.S. 148, 152, 85 S.Ct. 308, 13 L.Ed.2d 199 (1964); see also 15A Charles Alan Wright, Arthur R. Miller & Edward *460H. Cooper, Fed. Practice & Procedure: Jurisdiction § 3913 (2d ed.1992). We therefore turn to the merits of plaintiffs’ claims, recognizing that in the mine run of decisions remanding to an agency, § 1291 will foreclose a private-party appeal.
III.
Plaintiffs allege that the district court erred in vacating Notice 2006-50 and remanding, without specifically instructing the Service to promulgate a new refund procedure. When, as here, a rule is promulgated without notice and comment, the APA directs the court to “hold unlawful and set aside [the] agency action.” 5 U.S.C. § 706(2). The APA also permits a court to “compel agency action unlawfully withheld.” Id. § 706(1). But that provision applies only to “discrete action” that is “legally required ... about which an official had no discretion whatever.” Norton v. S. Utah Wilderness Alliance, 542 U.S. 55, 63-64, 124 S.Ct. 2373, 159 L.Ed.2d 137 (2004) (internal brackets and quotation marks omitted). Consequently, courts issue “detailed remedial orders” to an agency “[o]nly in extraordinary circumstances.” N.C. Fisheries Ass’n v. Gutierrez, 550 F.3d 16, 20 (D.C.Cir.2008).
Plaintiffs have not satisfied § 706(l)’s exacting requirements. 26 U.S.C. § 7422(a), which plaintiffs cite, at most requires some form of tax refund procedure. Yet one already exists. See 26 C.F.R. §§ 301.6401-1 et seq. Section 7422 does not come close to requiring what plaintiffs seek — a specific refund procedure for the telephone excise tax. Even if the code did require some excise-tax-specific procedure, it affords the Secretary of the Treasury great discretion to design the details: what procedural requirements to impose, how much time must elapse before a claimant may sue, and which forms may be used. Cf. Comm’r v. Portland Cement Co., 450 U.S. 156, 169, 101 S.Ct. 1037, 67 L.Ed.2d 140 (1981) (noting the Court’s “customary deference” to treasury regulations administering the tax code). Under Norton, that discretion forecloses the detailed order plaintiffs seek. 542 U.S. at 63-64, 124 S.Ct. 2373.
Plaintiffs argue that here, unlike in Norton, the Service has already acted and therefore must correct its error. But that distinction — between acting and failing to act — is irrelevant under the APA. Courts review both types of “agency action” the same way. Id. at 62, 124 S.Ct. 2373 (quoting 5 U.S.C. §§ 702, 704, 706). A court’s authority to remedy either type of error depends entirely on the underlying statutory obligation of the agency. Id. at 62-63, 124 S.Ct. 2373. Here, the only statutory failure was of notice and comment. Absent a statutory duty to promulgate a new rule, a court cannot order it.
IV.
A.
This brings us to the request for attorney’s fees. The government contends that plaintiffs may recover attorney’s fees only under 26 U.S.C. § 7430, which applies to “proceeding^] ... [brought] in connection with the determination, collection, or refund of any tax.” Plaintiffs argue that the general fees provisions of the Equal Access to Justice Act, 28 U.S.C. § 2412(b) & (d), apply.
Both statutes allow only a “prevailing party” to recover fees. A prevailing party is one who obtains a “material alteration of the legal relationship of the parties” through a “judgment on the merits” or a “settlement agreement enforced through a consent decree.” Buckhannon Bd. & Care Home, Inc. v. W. Va. Dep’t of Health & Human Res., 532 U.S. 598, 604, 121 S.Ct. 1835, 149 L.Ed.2d 855 (2001) *461(internal quotation marks omitted). Gurrola and Cohen, having failed to obtain either judgments in their favor or settlements, are not prevailing parties. Long-Distance Tel. III, 901 F.Supp.2d at 11.
Plaintiffs protest that this reasoning is overly formalistic because both Gurrola and Cohen raised potentially meritorious substantive challenges to Notice 2006-50 that the district court never reached. We disagree. One does not become a prevailing party “by simply filing a nonfrivolous but nonetheless potentially meritless lawsuit (it will never be determined) ... without obtaining any judicial relief.” Buckhannon Bd. & Care Home, 532 U.S. at 606, 121 S.Ct. 1835. Gurrola and Cohen never obtained “judicial relief’ and so they are not entitled to fees.
Sloan is a prevailing party. But we do not decide whether her request for fees is governed by 26 U.S.C. § 7430 or 28 U.S.C. § 2412 because she cannot succeed under either provision. A party may not recover fees under § 7430 without first exhausting administrative remedies. Sloan does not argue that she has done so here. That leaves § 2412.
B.
Sloan argues that she may recover attorney’s fees under 28 U.S.C. § 2412(b), which makes the government liable for fees “to the same extent that any other party would be liable under the common law.” She invokes the common benefit theory, which applies when “the burden of litigation ... benefitted others who in equity should share the expenses.” 10 Charles Alan Wright, Arthur R. Miller & Mary Kay Kane, Federal Practice & Procedure: Civil § 2675 (3d ed.1998). But that theory “ill suits litigation in which the purported benefits accrue to the general public” and is available only when “the class[ ] of beneficiaries [is] small in number and easily identifiable,” “[t]he benefits c[an] be traced with some accuracy, and there [i]s reason for confidence that the costs c[an] indeed be shifted with some exactitude to those benefiting.” Alyeska Pipeline Serv. Co. v. Wilderness Soc’y, 421 U.S. 240, 264 n. 39, 95 S.Ct. 1612, 44 L.Ed.2d 141 (1975); see also Grace v. Burger, 763 F.2d 457, 459-60 (D.C.Cir.1985) (holding that “the common benefit theory is inapplicable in cases ... where plaintiffs seek injunctive relief against the government” (quoting Trujillo v. Heckler, 587 F.Supp. 928, 930 (D.Colo.1984))).
None of the Alyeska Pipeline criteria are satisfied here. The class of beneficiaries of this litigation is potentially massive, including millions of taxpayers who used telephones. But that class is nearly impossible to ascertain with any precision because it excludes taxpayers who already claimed a refund and those who were never entitled to a refund. Even if the class could be identified, the benefits of the litigation cannot be estimated, much less determined with exactitude. That is because Sloan did not secure refunds but, at most, made it slightly easier to obtain one. Sloan makes no attempt to estimate the value of the procedural benefit her litigation actually conferred.4
C.
Sloan also argues that she is entitled to attorney’s fees under 28 U.S.C. § 2412(d), which awards fees to parties prevailing against the government “unless the court finds that the position of the United States was substantially justified.” *462Whether the government’s position “was substantially justified shall be determined on the basis of the record (including ... action or failure to act by the agency upon which the civil action is based) which is made in the civil action for which fees and other expenses are sought.” Id. § 2412(d)(1)(B). The government’s position is substantially justified if it is “justified in substance or in the main — that is, justified to a degree that could satisfy a reasonable person.” LePage’s 2000, Inc. v. Postal Regulatory Comm’n, 674 F.3d 862, 866 (D.C.Cir.2012) (quoting Pierce v. Underwood, 487 U.S. 552, 565, 108 S.Ct. 2541, 101 L.Ed.2d 490 (1988)). Substantial justification is a “multifarious ... question, little susceptible of useful generalization.” Underwood, 487 U.S. at 562, 108 S.Ct. 2541. Because the inquiry is fact-intensive and “the district court may have insights not conveyed by the record” we review decisions awarding or denying fees under 28 U.S.C. § 2412(d) for abuse of discretion. Id. at 557-63,108 S.Ct. 2541.
Although the question is close we do not think the district court abused its discretion in denying fees. The district court found the government’s position to be substantially justified because several circuit judges agreed with the government and dissented from the Cohen I and Cohen III opinions. Long-Distance Tel. II, 901 F.Supp.2d at 12.
Sloan cites opinions suggesting that an earlier dissent does not conclusively show the government’s position was substantially justified. But those cases acknowledge that prior dissents are still “properly considered when conducting th[e substantial justification] inquiry.” Friends of Boundary Waters Wilderness v. Thomas, 53 F.3d 881, 885 (8th Cir.1995); see id. at 884-86; EEOC v. Clay Printing Co., 13 F.3d 813, 816 (4th Cir.1994).
Here, the existence of several dissenting opinions is particularly persuasive evidence of substantial justification for two reasons. First, the court granted en banc rehearing, which is reserved for “question^] of exceptional importance” or to preserve “uniformity of the court’s decisions.” FED. R. APP. P. 35(a). If existing law had plainly favored plaintiffs, there would have been no cause for en banc review, even of a high-stakes problem. See Coal. for Responsible Regulation, Inc. v. EPA, No. 09-1322, 2012 WL 6621785 (D.C.Cir. Dec. 20, 2012) (Sentelle, C.J., concurring in the denials of rehearing en banc).
Second, the legal issues in the earlier appeals were difficult and amenable to reasonable disagreement. Whether Notice 2006-50 was a reviewable final rule or a policy statement, Cohen I, 578 F.3d at 6-12, is an amorphous and challenging legal question. See Cmty. Nutrition Inst. v. Young, 818 F.2d 943, 946 (D.C.Cir.1987). Similarly, the meaning of the Declaratory Judgment Act is hardly self-evident, because the Act’s text is “intrinsically ambiguous.” See Cohen II, 650 F.3d at 727-31.
Against that evidence of substantial justification, Sloan argues that the Service unjustifiably failed to acquiesce to the Eleventh Circuit’s American Bankers decision invalidating the excise tax. See Am. Bankers Ins. Grp. v. United States, 408 F.3d 1328 (11th Cir.2005). But that conduct is irrelevant because it did not occur “in the civil action for which fees ... are sought.” 28 U.S.C. § 2412(d)(1)(B). Furthermore, Sloan conceded at oral argument that the government complied with the American Bankers court’s order. See Oral Arg. Tr. at 14:20-17:5. We have recognized agencies’ rights not to acquiesce in one court’s legal conclusions in a different case. Indep. Petroleum Ass’n of Am. v. Babbitt, 92 F.3d 1248, 1261-62 *463(D.C.Cir.1996) (Rogers, J., dissenting); see id. at 1260 n. 3 (majority agreeing). Sloan also argues that the Service’s position was not substantially justified because it promulgated Notice 2006-50 without notice and comment. Standing alone, a notice and comment violation establishes that the government’s conduct was arbitrary and capricious. But “arbitrary and capricious conduct is not per se unreasonable” for purposes of attorney’s fees. Andrew v. Bowen, 837 F.2d 875, 878 (9th Cir.1988).
It is true that the panel and en banc majority opinions described the Service’s position in harsh terms. On that basis, one might reasonably conclude that the Service’s position was not substantially justified. See, e.g., LePage’s 2000, 674 F.3d at 867-68. But one might also reasonably conclude that, absent other factors, dissenting opinions on difficult questions are sufficient evidence of substantial justification. We therefore cannot say that the district court abused its discretion. The judgment below is
Affirmed.
. Fortis, Inc. v. United States, 447 F.3d 190 (2d Cir.2006) (per curiam); Reese Bros., Inc. v. United States, 447 F.3d 229 (3d Cir.2006); Am. Bankers Ins. Grp. v. United States, 408 F.3d 1328 (11th Cir.2005); Nat’l R.R. Passenger Corp. v. United States, 431 F.3d 374 (D.C.Cir.2005); OfficeMax, Inc. v. United States, 428 F.3d 583 (6th Cir.2005).
. Cohen (but not Gurrola or Sloan) also appealed the dismissal of his refund claims. We affirmed that part of the district court’s judgment. Cohen v. United States, 578 F.3d 1, 14-15 (D.C.Cir.2009).
. Plaintiffs do not argue that the denial of attorney's fees is, in itself, a final appealable decision. See Pigford v. Veneman, 369 F.3d 545 (D.C.Cir.2004).
. In her reply brief Sloan seems to suggest Alyeska Pipeline's criteria do not apply because the government is not entitled to the money it collected under the excise tax. Sloan has not cited, and we have not found, any authority supporting that argument.