Bisping hurting Silva with a punch is perhaps the least likely outcome possible and if you believe that I don't value your fight analysis highly. Even if Silva is waaay, way out of his prime, Bisping knocking him out is extremely unlikely. We don't know how much Silva has declined, if any so we'll have to wait and see how he performs. Losing to Weidman means nothing in terms of how he'd do against someone like Bisping. The Diaz fight sucked as much as the Leties fight and Silva has from time to time put on awful performances mostly due to the type of fighter he's faced.
Really looking forward to this fight to see if Silva still has the ability to fight his way to a title shot. Too many are counting him out because of his losses to Weidman, a guy many thought was the MW GOAT.