If the intent of that question is to determine whether there's a "win" for pro-RKBA folks, and a "win" for anti-RKBa folks, then the answer must be "no," almost by definition. A win on the pro-gun side is automatically a loss for the anti-gun side, and vice versa.
No: This is true only if opponents and proponents share the same utility function. I believe that's unlikely, and the preamble to this thread asked it to be assumed for the purposes of discussion. In my example, I suggested that the single most-valuable restriction RKBA opponents would like to add is a ban on "large-capacity" magazines. Maybe this is incorrect -- we could discuss better examples, though based on what I hear from the gun-grabbers I don't think it's a bad one.
Now, for RKBA proponents is the right to continued commerce in magazines of unlimited capacity the single most important element of the RKBA? Maybe, but if you practice magazine changes I'm guessing it isn't. As I said, I personally would rather live in a world without many NFA restrictions. This is an example of a win-win
: For some reason opponents think high-cap mags are the biggest affront to decency in the democratic world, yet most of them don't even know what an SBR is or what a suppressed gun sounds like. I practice tactical mag changes, so having to drop mags after 10 or 20 rounds instead of 30, 50, or 100 is much less of a concern than being able to equip all my guns with cans, or put a folding stock on my pistol without commiting a felony.