DECISION
KASTL, Senior Judge,The knotty crime of conspiracy — and what admissible matter is sufficient to prove it — is before us today. We find that *733the trial judge erred by treating an offer of proof as evidence over defense objection. The offer of proof came from Captain W, a defense lawyer at an earlier court-martial; it purported to reveal the appellant’s conspiratorial statements.
Airman Basic Kilbourne, the appellant, was convicted by a general court-martial with members of wrongful use and distribution of lysergic acid diethylamide (LSD) and conspiracy to commit the offense of perjury, violations of Articles 112a and 81, UCMJ, 10 U.S.C. §§ 912a, 881. Her sentence is a bad conduct discharge, total forfeitures, and confinement for two years.
The Government’s theory as to conspiracy was essentially this: Kilbourne was heavily involved with LSD, together with Rosato and Bly. When military authorities became suspicious, the trio concocted a lie to exonerate Kilbourne. They would swear falsely that: (1) the appellant and her friends tired of Bly bragging about his drug exploits; (2) to trick him, they cut up an ordinary carry-out bag from the local Burger King into tiny pieces; and (3) they were guilty of no more than mischievously telling Bly it was coated with LSD. The three agreed to tell this fictitious tale in court — provided they received grants of immunity.
Bly was under charges. He suggested that his trial defense attorney, Captain W, speak with the other conspirators. They advised Captain W of their scheme. Realizing she could not ethically present perjured testimony, Captain W revealed to the military judge that the appellant and Rosario were prepared to lie under oath.
In the present court-martial, the defense moved in limine to bar admission of the pertinent portion of Bly’s record of trial containing Captain W’s averment. The military judge ruled the transcript admissible as a public record under Mil.R.Evid. 803(8). He expressly rejected the defense contention that averments of counsel were not evidence for subsequent trials.
We hold that the military judge erred in admitting the averment of Captain W in the present court-martial. An averment or offer of proof is not evidence; it cannot stand when, as here, an opposing party objects. United States v. Eastman, 20 M.J. 948, 950 (A.F.C.M.R.1985). See also United States v. Thompson, 11 U.S.C.M.A. 252, 29 C.M.R. 68, 71 (1960); United States v. Boney, 45 C.M.R. 714, 716 (A.F.C.M.R.1972); United States v. Cummings, 21 M.J. 987, 989 (N.M.C.M.R.), pet. denied, 22 M.J. 242 (C.M.A.1986). The fact that the averment is enshrined within an authenticated record of trial does not transform it into evidence. Nor can the fact that Captain W was an officer of the court somehow spin this straw into gold.
The Government argues that even if we find Captain W’s averment inadmissible, any error in admitting it at trial was harmless. After all, says the Government, similar information was available from Airman Rosato, a co-conspirator, who testified as to the conspiracy at the present trial.
We disagree. Factually, we find Rosato’s testimony contains insufficient data upon which to sustain a conviction.1
*734II
The appellant argues that error occurred when the prosecution was permitted to bolster Rosato’s credibility prior to it being attacked. We find no error here, especially since the defense effort which followed was a wholesale attack on Rosa-to’s character and motives. See generally United States v. Boone, 17 M.J. 567, 569 (A.F.C.M.R.1983); United States v. Harvey, 12 M.J. 501 (A.F.C.M.R.1981); DA Pam 27-22 Evidence, paragraph 7-2 (15 July 1987). As we read this portion of the record, it should have been self-evident to all that Rosato was far from a “clean” witness and that his veracity would soon be challenged.
We view Rosato’s direct testimony here as typical of witness assertions that “My lawyer didn’t put words in my mouth; he only advised me to tell the truth.” Even more significantly, the witness was opining that he might lose the benefit of a pretrial agreement if he perjured himself. We see his testimony as nothing more than the usual see-saw effort of competing counsel seeking to place their witnesses in the best light. Even assuming error through “improper bolstering,” we would in any event discern no error affecting the appellant’s substantial rights. Article 59(a), UCMJ, 10 U.S.C. § 859(a).
III
The prosecution tactics at trial draw another assignment of error: Kilbourne alleges that the prosecutor both impermissibly commented on her failure to take the stand and engaged in unfair argument.
During his findings argument in rebuttal, the prosecutor rhetorically asked why the appellant had failed to testify at the trial of an airman named Heishman. Heishman apparently was also involved in similar goings-on. The defense promptly objected and requested a 39(a) session.
Trial counsel explained that he never intended his comment to reflect adversely on the appellant’s Constitutional right to silence. Instead, he explained, he was alluding to the unbelievability of the appellant’s defense: She was defending today on the basis that the “prank” with the Burger King bag was true — if so, why hadn’t she come forward in the earlier trial of Heishman, who was similarly involved, to say so? The military judge cautioned that any comment on an accused’s silence was improper. He then denied the appellant’s request for a mistrial, proposed a curative instruction, received instructional input from both sides, and recalled the members. The military judge then gave what we regard as a firm, tailored instruction and received individual responses from each member that they could follow his instruction.
We find no reversible error. It is horn-book law that a mistrial is mandated only when manifestly necessary in the interest of justice. See R.C.M. 915(a); United States v. Dennis, 16 M.J. 957, 965 (A.F.C.M.R.1983). From the record, we are convinced that the military judge’s firm curative instruction, together with the assurances of all the members that they would follow his guidance, corrected any possible error. See United States v. Fitzpatrick, 14 M.J. 394, 397-398 (C.M.A.1983).
Nor do we find reversible error from other arguments of the prosecution. This was a splendidly tried and defended case, with advocates who brought evident flair and ability to the courtroom. The complained-of prosecution language, we believe, constituted fair comment. United States v. Doctor, 7 U.S.C.M.A. 126, 21 C.M.R. 252 (1956). Moreover, the lack of objection by defense counsel is some indication of the minimal impact of such remarks on the court members. See United States v. Arnold, 6 M.J. 520 (A.C.M.R.) pet. denied, 6 M.J. 157 (C.M.A.1978); United States v. Eggleton, 48 C.M.R. 505 (A.F.C.M.R.1974).
*735IV
The appellant argues that the military judge erred by failing to grant a mistrial after the assistant trial counsel commented on the appellant’s failure to express sorrow during her unsworn statement. See United States v. Chaves, 28 M.J. 691 (A.F.C.M.R.1989). We reject the appellant’s argument. Chaves provides guidance as to appropriate sentencing factors upon which the military judge properly might instruct. The case does not concern itself with what can be advanced by advocates during their closing statements. United States v. Gibson, 30 M.J. 1138 (A.F.C.M.R.1990).
V
The other assignments are resolved adversely to the appellant.2
VI
Finally, we are invited to consider the matter of sentence appropriateness. We first take corrective action based on our determination that the Government failed to offer sufficient evidence on the offense of conspiracy to commit perjury. That offense is contained at Additional Charge II and its specification; they are dismissed. Reassessing on the basis of the remaining offenses, we find appropriate only so much of the sentence as extends to a bad conduct discharge, forfeiture of all pay and allowances, and confinement for 20 months. As for the reassessed sentence, we find it befitting for this appellant, her extenuation and mitigation, and the remaining matters of which she was found guilty.
The findings of guilty and the sentence, both as modified, are correct in law and fact and, on the basis of the entire record, are
AFFIRMED.
Senior Judge MURDOCK concurs. Judge MILLS did not participate.. We have decided this case upon an evidentiary ground — that the averment of counsel before the Kilbourne court-martial was inadmissible, thus leaving an insufficiency of proof as far as the conspiracy charge is concerned. Yet even assuming, arguendo, that there was sufficient proof, we would have some doubt whether this alleged conduct satisfies the definition of conspiracy under military law.
The conspiratorial activity did not necessarily progress beyond mere preparation. Moreover, the contingency needed to kick off the conspiracy (the grant of immunity) did not exist at the time the parties revealed their plot to Captain W.
Military practitioners should be aware of the pitfalls in this difficult area. Research is even more challenging because few "pure” conspiracy cases exist without an underlying substantive offense. See Yawn, Conspiracy, 51 Mil.L. Rev. 211, 224 (1971).
Initially, there can be no doubt conspiracy to perjure is chargeable. See, e.g., United States v. Clark, 11 M.J. 179 (C.M.A.1981); United States v. Schwab, 27 M.J. 559 (A.C.M.R.1988). But when military conspiracies are analyzed, the prosecution seems to have its work cut out in sustaining a conviction. See, e.g., United States v. Kauffman, 14 U.S.C.M.A. 283, 34 C.M.R. 63 (1963) (espionage); United States v. Yarborough, 5 C.M.R. 106 (C.M.A.1952) (self-inflicted injury); United States v. McGlothlin, 44 C.M.R. 533 (A.C. *734M.R.1971) (pandering). See generally MCM, Part IV, paragraph 5c(4)(a).
Further sources are 16 Am.Jur.2d Conspiracy (1979) and 15A CJS Conspiracy (1967). See also United States v. Messerlian, 832 F.2d 778, 796 (3d Cir.1987); United States v. Perlstein, 126 F.2d 789 (3d Cir.1942), cert. den. 316 U.S. 678, 62 S.Ct. 1106, 86 L.Ed. 1752 (1942); United States v. Bufalino, 285 F.2d 408 (2d Cir.1960).
. We still receive a few records of trial where there is no clear-cut indication of precisely which court members named in the convening orders are present. The difficulty perhaps lies in the imprecise language employed in Air Force Regulation 111-1, Military Justice Guide, para. 14-9 (9 March 1990).
When the members are not listed, as in this case, considerable appellate time must be expended in rechecking the voir dire, the "number of votes required” comments, and excusáis to insure that all members are accounted for. We urge military judges, trial counsel, and court reporters to handle this problem. A few seconds of extra time at the trial level will save a grateful Court unnecessary "busy work.” United States v. Hayes, 24 M.J. 786, 792 (A.C.M.R.1987); see MCM, App. 8, Sec. II at A8-10 (1984); DA Pam 27-9, Military Judge’s Benchbook, para. 2-23 (May 1982); United States v. Staton, 48 C.M.R. 250 (A.C.M.R.1973).