I haven't seen Moore v Marciano in ages but, from what you describe, I can see what he is trying to do. And you are spot on when you say that it is easier to anticipate and counter when you make him throw the punch you want. Personally I think you can do the same thing by stepping with the left foot only as you jab, then stepping back. But Moore was in the ring and I would never dare to question his tactics. Do you know if he fought Durelle, or anybody else, that way?
One of my closest friends has sparred many rounds with Mayweather and we have talked about this often. He rock's up on the jab, which stops the guy over there, you know? Then he rock's back to his right foot, creating distance and leaving him ready to land the right when you try to close. My thought is that you need to time his jab with your own, his rock forward with a push off. You land a jarring punch or you close on him as he rock's back; as you slip his jab you take your head away from his right and control his left shoulder.
My friend pointed out that,1, Floyd plots each move well in advance,2, when you do outsmart him he is very fast and elusive and,3, it is very difficult to fool him the same way twice.
You are dead right when you say that there is more than one way to do things. Ultimately the 'right' way is the one that works. When you are teaching it to somebody starting out, you teach to an ideal. As the boxer gains experience he developed ways of doing things based on his strengths and weaknesses. As his trainer you have to observe this, keep working on weaknesses so they don't become limitations, and help him learn his style.
I don't feel comfortable, in many situations, working with an experienced fighter until I see him in the ring. Then I can get a feel for what he is trying to do And how he is looking to do it. Then I can tighten his footwork, work on his right hand, or, most important, talk strategy.
If that makes sense.