The skills nowadays don't matter this much... This season I trained 2 players, one from 87% to 127% with 230 rests and one from 63% to 125% with a little over 300 rests.
They are no mutants, and a few months ago I would have trained them in a different way, but the white skills are between 150 and 200 % and the grey around 80-100%, still they performed quite well up to this point.
Overall quality with a little higher white skills for the win. lol