Assuming you're talking about the Gilberto that played for Tottenham, and not the Arsenal one. He was useless primarily because he was coming to the end of his career at 31 when he joined. Compared to Arsenal's Gilberto, who spent a lot of years at the club, and played regularly for them. Kleberson was useless because he was hardly used by Man United. He couldn't push out Paul Scholes for a regular place, while Robinho, although he had good spells at Man City, he fell out with Mark Hughes and then his form dropped. However, i do agree with you about Jo. Hopefully, if they're treated with respect, Ramires and Neymar won't be in the same boat as all of the above.