If Yoda and Obi-Wan fought the Emperor during Ep.3

Would it had made a difference or not at all.

Depends, if Yoda and Obi were coordinated in their attack and planned on how they would take him, I think they could. However, you saw how easily Palpatine took down the other Jedi Masters Tin, Fisto and Kolar when they tried to arrest him… pretty half-a$$ed if you ask me. Anyway, I felt it could have gone either way, all depends as well if The Emperor would have called for backup. If so, Yoda and Obi-Wan's story would have been cut short.

I think they would've won. Yoda and emperor seemed pretty even and if they planned it out they definitely could've won. Obi wan could not take palpatine on his own but he would be enough help to give his team the win. Obi wan is the complete package when it comes to being a Jedi

Emperor would have won. He's alive in the next three movies...

No, Obi-Wan would just get in the way and Palps would have won anyway. Yoda said that Obi-Wan wasn't strong enough to fight the Emperor.

"Send me to kill the Emperor, I will not kill Anakin."- Obi-Wan

"To fight this Lord Sidious, strong enough, you are not."- Yoda

@wolfrazer: He wasn't exactly strong enough to take Maul on himself either.

Would not have made a difference at all.

Sidious would have speed blitz Obi-Wan like he speed blitz other Jedi/Sith in his speed class.

He was very slow... Obi-Wan looked a lot faster when he was fighting Anakin.

Obi's a non-factor.

Obi-Wan is strong, but he isn't powerful enough to make much of a difference. He's still severely outclassed.

This is pretty accurate. While it's possible Yoda would have intervened, it only would have delayed Obi-Wan's inevitable death.

@jedixman: I agree. Though, one could make a case that Obi-Wan presence would only hinder Yoda.