Lukaku this season reminds me massively of Rooney under Moyes. Productivity and general ability wise pretty good but just frustratingly inconsistent in terms of his technical play. You're spot on when you say that playing with him must be incredibly difficult. For five aerial balls in a row he will be completely outfought by the defender, whilst someone like Martial is running in behind hoping for the flick-on; then the 6th ball Martial will not make the run and Lukaku will win the header. The same is the case with his first touch and his dribbling play. In my view this is why he's not the best "team" player. He's at his absolute best when he's either a) finishing chances that other's feed into him; or b) using his pace and power to drive at the opposition defence, somewhat away from his teammates. It's also though why I think Lingard plays really well with him (and I'm hoping Sanchez will likewise), as I think he's the one player that will continue making runs irrespective of the frustration of not being found.