While I like O'Neill as a manager, if you're not playing reguarly, it doesn't matter how good the manager is. We have much better players that play in his position, and I'd play Milner, Petrov, Reo-coker and Delph all over Sidwell. He won't be a regular at Villa, so a move makes sense
Sidwell never impressed me when he did get his chances (which we're admittedly fairly limited.) I had such high hopes for him after remembering him from his Reading days, and when he scored that cracker against Wigan away coming off the bench in what I think was his debut(?)
Whether it's because his confidence has gone, or if he just doesn't fit into the system we play I don't know. Or maybe he just wasn't that good to begin with. It never worked out for him at Chelsea or Villa so I think Fulham seems the sort of standard I could imagine Sidwell playing at. He won't be a regular at Villa, so a move makes sense for both Villa and Sidwell. He can hopefully get his career on track and we won't be paying his wages.
