Could Hagler have fought at 154 with 24-hour weigh-ins?

Nah you do not understand man.
He was very lean, not fairly. Still, he routinely weighed in the late 150'a max. We would likely all agree that 154 would be the least he might make without a problem-if we were only talking about fat,
But unless he was dehydrating to an unusual degree for same day weigh ins-& there is no indication he was...

Guys routinely do 10% or more today,
He could take off & put on the water weight, because muscle is mostly water too.

Not that I think the whole process is healthy & most fair to all in the long run.
I would have same day weigh ins, within a couple hours of the fight.

 

It's not about training at that point it's about drying yourself out, Hagler would make 154 with ease.

 

Yep, this. Hagler was not a particularly large middleweight. If he had an extra day to hydrate he'd easily do 154.

 

I doubt Hagler would have been as effective at 154, even if he could have made the weight.

 

That's a point to consider.

 

Wish more people would consider the 'same day' vs 'day before' weights when making predictions/lists in Classic Forum. Game changers.

 

Well - I consider Hagler to be almost the perfect Middleweight, physically. In my view, there's a lot to be said for a boxer training and maintaining themselves at their optimum fighting weight.

I often think that the notion of a significant advantage being gained, if a boxer squeezes into a unnatural weight class, is akin to a false economy.

 

This. Hagler would’ve been weak at 154, since he’d have to dehydrate himself to make 154.