Poll
60%
40%
I can imagine, that both, Sidious and Vader instantly attacks Yoda with combo of force TK and lighhtning, before Windu would be able to react. Yoda might be able to recover quickly, doubt that in time though...
In a duel, Jedi takes this without much difficulty, Vader should be a weak link.
Anyway, it seems that sidious always has his first move, adding Windu's inferiority in terms of Force powers, Sith might take some majority.