I honestly don't think there is much to exploit though. Given the short time frame you're only going to gain a few lbs and dehydrating and draining yourself on the day of the fight for this debatable advantage is pointless.
Whether or not the fighter agrees is a different matter. It's obvious to me that a fighter would have 'the real edge' by coming at his fighting weight and being nutritionally prepared. Like you say though, it's human nature to explore other ways to gain an advantage - even if those ways are dangerous.
Problem is now, with the current weigh-ins some fighters are dehydrating themselves to a point where 1 day isn't long enough to re-hydrate. You're looking at 2-4 days depending on the degree of dehydration. It could be argued that the fighters are dehydrating to this degree because they feel a 24 hour window is plenty of time to re-fuel and rehydrate...which isn't always the case.
Bookmarks