If a prospect was playing video games all night, would his draft ranking be affected because of the effect on his on ice play? He would have no energy & would make a lot of mental errors, and probably not be drafted. So, not an issue.
Although I have to say that TT has the best job, get lucky once & you look great for years. If you don't draft anyone of significance, hey it's a crap shoot. Can't be blamed, the GM made us take him (even though you ranked him that high)/it's a gamble, etc... That must be why he is always smiling, because it can't be because of his selected prospect pool.