concurring: It seems to me that the rationale of decision under section 1235 should not be different whether the issue be field of use or geographic area of use. Such being the case, although I am not fully satisfied that our prior analysis of the meaning of "substantial rights” is wrong (see Mros v. Commissioner, T.C. Memo. 1971-123, revd. 493 F.2d 813 (9th Cir. 1974)), I am now willing to accede to the contrary analysis articulated by three Circuit Courts of Appeals. Estate of Klein v. Commissioner, 507 F.2d 617 (7th Cir. 1974), revg. 61 T.C. 332 (1973); Mros v. Commissioner, 493 F.2d 813 (9th Cir. 1974), revg. T.C. Memo. 1971-123; Fawick v. Commissioner, 436 F.2d 655 (6th Cir. 1971), revg. 52 T.C. 104 (1969). I reach this conclusion independently of Golsen v. Commissioner, 54 T.C. 742 (1970), affd. on another issue 445 F.2d 985 (10th Cir. 1971). See n. 4 of the majority opinion herein.
Drennen and Sterrett, JJ., agree with this concurring opinion.