I think it's more of a Mario wants Chelsea than Chelsea wants Mario. Jose might think he could polish him up and finally help him realise his potential. To be perfectly honest, I am not bothered about those little off field antics if he can show us some respect and perform like his life depended on it. A little misdemeanour here and there has always been part of football players.
If he is to come here it could only make sense in the summer. We would have got rid of Eto'o and Ba. And if Lukaku finally returns we have 3 top strikers of different styles. And moreover it would give Jose time to work with him and tame it a little bit. Jose may be thinking that when he needs to, he could pair Torres with either of the two. Just thinking.