He isn't. It's a complete misunderstanding of biology to suggest so. The fact of the matter is that it has been nothing to do with him being 'broken' or 'overplayed' which is nonsense, more that he has failed to do even the basics well enough when he's been on the pitch for them.
The reason behind this, is that, contrary to some of the rubbish you'll read on here, Tielemens is the type of player who must play every week and perhaps more if you want to get the best out of him. This is not happening at Villa so they'll never see him at his best until they get him into a rhythm. They can't do that unless they give him games and time which, given the performances of their midfield so far this season, isn't going to happen unless there is an injury.
I don't feel any real dislike towards the guy, I don't care much about him either way to be honest but if Villa want the best version of him, they won't get it in bit parts.