FTB,
I don't quite understand the logic on the snap-back statement. Snap-backs are given in return for concessions, in case the company does better than estimated, in the future. If you're after improvements, or getting imporvements, you generally don't want snap-backs. The company might want snap-back-downs, but I don't see how/why we could have negotiated snapbacks in LOA 19. We needed them in LOA 46 and 51, but those were the bend-over contracts, remember? It's pretty clear to me why we didn't get them back then. Was that before your time?
The mechanism often used to get more when times are better, when used in conjuction with contractual improvements, is often profit-sharing, something we already negotiated. I'd like it to be more, but the kind of variable adjustment you describe is already present, even if not enough in amplitude.