standard of heavyweight boxers or the standard of the trainers?

I find it miraculous that time after time heavyweights are sent in against the Klitschkos with no feasible game plan. Mormeck essentially was sent out to do nothing but get hit, he was never going to win obviously, but surely tell him to at least stay low and use what he had to his advantage. I cant understand why trainers wont use a shorter heavyweight to try and bob and weave inside, work the body etc. Frazier and Tyson both used it well but it seems that style has been completely abandoned, i cant think of a heavyweight recently with even a resemblance of decent head movement while on the offence, baffling.