It happens all the time the pros call it anticipating contact but I would call it cheating or diving, the reason Shearer agreed with it is he used to do it.
Here is Rooney doing the same thing he is on the ground before there is any contact --
I havent seen the Bent 'penalty', but the Rooney incident, even looking at it in slow motion would be a penalty 9times out of 10. The reason, he rounds the ball past the keeper and the keeper nails him! simple...
Do you see where shrek hits the ball...he was never going to get it, just make sure you hit it anywhere before the keeper can get it. Job done, top cheat.
As stated previously, he hits the ball past the keeper and keeper nails him... Defo 9/10 times a penalty... There is no denying the keeper takes 'shrek' out of the game in the penalty box... penalty!
I would say shrek's started to dive before any contact. He was definitely looking for a penalty. Difficult for the ref to spot, but with a 4th official and slow motion it could be seen.