Anakin with a clear mind like when he fought Dooku could take on and beat anyone - Yoda included. When he turns to the darkside and is in the same state of mind as when he fought Kenobi he is not fighting to his full capacity, so the likes of Yoda, Mace, Sidious and Obi-Wan would still be able to beat him.
I would agree to this, but ONLY in terms of saber combat. Yoda (and Sidious) would still be able to beat Anakin in a force battle even if Anakin was having his best day.
Nah man, a clear-minded Anakin is weaker than when he is immersed in the Dark Side. He uses his anger, frustration, and emotions to help with his fighting. He uses the Dark Side to guide his fighting, just like any Jedi would use the Light Side. He used this against Dooku the second time they fought and won because of it. He also used it against Obi-Wan and failed.
So Obi-Wan can beat Anakin. Also I think Dooku could take Anakin if Anakin doesn't go into a fking berserker mode and smash Dooku into submission.
__________________ Thanks to Pittman for the sig
"I don't care if I fall, as long as someone picks up my gun and keeps on shooting." -Ernesto Guevara.