So make one significantly better...the other significantly worse, and then "see what happens"...seriously? I mean yeah I guess that would change things...but here in reality, the bottom line is PBF is the better fighter by any metric concievable, so I'm not sure what exactly you're getting at.
As far as the lower weight, Floyd was faster and had more power at lower weights, so I'm not sure how going down in weight benefits Juan? Look I love JMM as a fighter and have nothing but respect for him, but there is nothing he brings to the table that is going to bother Floyd anymore than he did. He's a great counter puncher...Floyd doesn't waste punches and get caught that way. Furthermore Floyd's reflexes and anticipation are too good for Juan to time him. Athletically there's really no comparison, especially at lower weights. Defensively...nothing to debate Floyd is far better. I mean I struggle to digest how or in what way JMM would significantly trouble Floyd...any version.