Tevez wasn't used before because he wasn't in form. The Rooney/Berbatov partnership was going good for us. We're not like Liverpool, we don't pay big money for players to sit on the bench. At first I was unimpressed with Berbatov, but with more playing time in the first team he's adapted to our system very well.
Unlike Keane, Tevez is actually wanted by Fergie, but the stumbling block is obviously the price put on him by MSI. In such times, it's difficult to fork out another 30million or whatever it is to sign Tevez. It's sad, I'd hate to see him leave, but I still hope that he'll stay, however unlikely it will be.
You can only accommodate so many forwards at the same time. Tevez will never displace Rooney, because an Argentinian will never be picked over an Englishman at an English club unless Rooney was really shit. But at least Tevez gets put on the bench. And when called upon, will contribute to our title chase, as evident in the game against Stoke. Unlike Rafa, who doesn't even put him on the bench mostly.
Keane is definitely not a second rate striker by any means. He's got talent, and he can score goals. He also had leadership qualities that Spurs will find handy right now. We're getting away with our lack of scoring because of our excellent defence. Liverpool does not possess the same defensive quality. Even then, you can't rely on your defenders every week to get you out of jail. When you find that Gerrard and Torres aren't scoring (like the weeks before), Liverpool will drop points. You can't afford to lose too many points when you're playing catchup.
