If Futch had trained Tyson, assuming Eddie would risk the potential aggravation, and that Mike would listen.....
There would have been no time wasted trying to find the " old" Tyson. Futch would have stopped him being so square up and got him more sideways, left shoulder out front. That puts his head six inches or more further away from an opponent's jab and that helps a town reflexes that aren't what they once were. The shoulder out front would make it easier to execute what has to be the Eddie Futch signature move; rolling inside a right hand a coming back with a right uppercut. Every Futch fighter but Frazier used that move.
He would have Tyson always shading to his own right- easier to slip in then weave out to the right, out of range. Plus, he would want those tall heavies turning over their lead foot, not moving behind it, like if Tyson were in front of them. He would be wanting those guys punching across themselves to give Mike a better shot to make a move and land something big.