You don't play one on one when faced against the big sides, so it doesnt help a lot that he can skin great fullbacks. Youre also playing against great coaches. And decision making is not just to make the right cross after you skin the fullback, but also before that to figure out ways to not be predictable to the opposition. And that is through your movement. Through that youre creating and recognizing the moments that you can exploit due to the situation rather than starting every move with "ok Im just standing here and Im better one on one against this defender so they just need to give me the ball and something will happen". The opposition always has a backup plan that you need to take into account too. End product will come naturally once he figures out how to anticipate situations better, be more creative with his ability and think out of the box.