Whether Wenger encourages Song or not, and I don't think he has ever explicitly said that (he said something along the lines of "he's positioned further forward because we want him further forward", but I remember it being related to goal kicks or only at the start of games, something that muddied the waters. Wenger has also said numerous times that Song is THE holding midfielder in the team, the sitter, the deepest midfielder), Song makes poor, selfish, careless, irresponsible and sometimes downright stupid decisions constantly in every game he ever plays, and it costs us defensively. No player is perfect, but some players are less perfect than others, and I think we could really do with a smarter, more disciplined, more aware player playing in Song's role.