In boxing, if guy (a) holds a belt at one weightclass and goes up/down a weight to face guy (b) who's also a title holder and guy (b) can legitimately make the weight class guy (a) has come from, both belts have in the past been on the line.
So in theory, they are fighting for two (or more) belts in two weight classes.
How would the unified rules accomodate this and could they (not to mention would Dana/UFC entertain it)?
Best example i can think of that could realistically happen is Jose Aldo vs Frankie Edgar. Now both guys can make both LW and FW easily, so if the two were to fight still as champions (at either FW or LW) then in theory both belts could be on the line, couldn't they?
I don't recall it ever happening in MMA, we've had champ vs champ but there's always been one guy that'd never make the lower weight, for example Rampage vs Hendo, GSP vs Penn etc.
As for the theoretical Aldo vs Edgar fight, if it ever did happen i could only see one guys belt on the line, despite both belts being a legit option.
Just something my tiny brain was considering today, your thoughts???