I think that same day weigh-ins would be a good thing; even better, there used to be title fights with stipulations of a weigh-in three hours before the fight. Really nothing wrong with getting in shape and making the weight your are contracted to make. I remember McClellan coming into the ring in the 185-190 range- a small heavyweight, not a 'big' middle.
I'd be interested to know how many of those injured were at a considerable weight disadvantage- like Gamache/Gatti.