More than anything, was the catchweight a business move.....

The only way your theory pans out is if this fight is in fact competitive. Lets say Canelo wins 5 rounds on the scorecards but shows signs of gassing out late. that would make people think that had the cw not been in place he would of been able to swing 2 rds in his favor and thus possibly won had he not dropped 2 extra pounds at the weighin. Problem with that is if the fight is that close I dont see Floyd wanting any rematch whatsoever.

Nope, Floyd did it cause the so called pfp king (Floyd), needed some kind of advantage, kinda like what Pacman used to do. Same thing, different so called pfp king.

His camp raised some concerns about Canelo rehydrating to 172, which prompt him to do the catch weight. Floyd didn't want to be at too much of a size disadvantage, all there was to it. The 147 proposal was simply leverage, I think all parties knew 152 would do it in the end.