That's a slightly different issue, Mike. That one deals with whether the commercial dual cross countries can be done IFR. Before the amendment, the answer was no; after the amendment, the answer is yes.
The question being asked, however, is whether one can "double dip" the 61.65 and the 61.129 cross countries. On that, I think the answer is "maybe." Here's the problem (and a verrrry long explanation, but I think it's important to CFIs to understand it as a benefit to their students):
There's a long line of thought in the FAA that one can't use tasks meant for one certificate or rating to satisfy the requirements of another. In the old, orphaned FAQ, John Lynch expressed this as a dislike for "double-dipping" (the reasons I used that term at the beginning). The no-double-dip concept was later adopted by the Chief Counsel's office in opinions like 2011's
Murphy opinion (a 2-hour student pilot cross country can't be used to meet the commercial dual cross country requirement).
Even more to the point is the 2010
Hartzell opinion. In that one, the Chief Counsel reaffirmed the Theriault opinion (also referenced in Murphy). In that one, the Chief Counsel reaffirmed that 61.65 instrument training
cannot be used to satisfy commercial requirements. Same concept, different application.
"There is not an exact equivalence between the training required for an instrument rating under §61.65 and the aeronautical experience requirements under §61.129."
The underpinning for all this is the "on the areas of operation" language that appears as part of the training requirements for (just about?) every certificate or rating. Even if they sound the same, the "preflight preparation" task for the commercial is at least qualitatively different than the "preflight preparation" task for the private and the "preflight preparation" task for the instrument rating.
drunkenbeagle mentioned doing a combined 61.65/61.129 cross country. I think that works because, fortunately, Hartzell provides a possible way out of the dilemma. It's about the documentation: if the instrument dual is intended to also meet a commercial dual requirement, it needs to be documented in a way that makes the intent clear.
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The Theriault interpretation reinforces the existing requirement that instrument training used to satisfy the aeronautical experience requirements under §61.129 needs to be clearly documented by the applicant for the commercial pilot certificate. The interpretation dispels the notion that holding an instrument rating is, on it’s own, sufficient evidence that the applicant has fulfilled the aeronautical experience requirements for a commercial pilot certificate under §61.129. However, we anticipate that for commercial pilot applicants who already hold an instrument rating, the hours of instrument training used to obtain that rating will meet at least some, if not most, or quite often, meet all the requirements for instrument aeronautical experience as required under §61.129.
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So it at least looks like the answer to the OP is a strong "maybe." Was the 61.65 dual instrument cross country endorsed or written up by the CFI in a way that makes it "clearly documented" that it was intended to include the commercial "areas of operation" cross country tasks. Yes, I think it's okay. No, I think there's a problem with "double dipping" it.
