Solano was probably our next-best player after Martins that season. We had Solano, Milner, N'Zogbia and even Dyer who could occupy a wing spot. A winger would've been useful, but Duff turned out to be an absolutely terrible choice. Mourinho (right?) obviously knew what he was doing when he sold that piece of shit.
Dyer was totally wasted out wide, Milner was expected to leave that summer, only staying because of last minute problems with the Viduka signing and Solano played at RB the season you're on about. His days on the wing were done.
Duff was awful for us, but anyone who claims to be disappointed with the signing at the time (apart from Wullie, who rated N'Zogbia as the next Figo) is kidding themselves a bit.