He damages our ability to get the ball forward and make it stick as a cohesive unit. That's what I mean by damaging us; and it isn't a myth, it's still being played out. He could score 30 goals and wouldn't make any difference to that issue; they are two completely separate things, as he could score two a game and we'd lose 3-2 because he'd be anonymous beyond popping up twice.
People realise what he is, and that's why some people like myself would rather we played to his strengths rather than his weaknesses, or if we are to continue playing to his weaknesses, then bring someone in who that play would be a strength to instead and thus improve the whole side.
Let me put it as bluntly as I can - he's the second highest goalscorer in the league right now, in between Costa and Sanchez, yet those two players are multitudes better footballers than Lukaku. Chelsea and Arsenal would be mental to replace either with Lukaku, because the entire flow of their side would be changed and they'd become porous at the back as a result. That's why Lukaku is not at a top team - not because only a few clubs can afford him, but because those clubs don't see the point in spending that much on what would be a liability in how they play. Top clubs play from back to front; Lukaku, sadly, doesn't have that in his game consistently enough, and that's true not just at the top level but at the level we are at too.
Our best hope is one of two options - we either build around him and develop a top side in a way completely unlike every other top club currently in the world, or we get top dollar for him from a club more rich than smart and build around Barkley. If we can get £60-70m for Lukaku, I really wouldn't mind the latter, but if we really could get a system where Lukaku scores and isn't responsible for taking the ball to feet and holding play up in the final third, then that'd be fantastic too.