i agree with much of what you say, and i don't think Sidious owns Yoda, just that he was a the same level. i agree with Yoda blocking Sidious best, but what did Yoda do, trying to kill/defeat Sidious? almost nothing.
Yoda was on the defense for the main parts of the duel. Only through the light saber fight we see sidious having smallproblems, but he quite easily defend, until Yoda JUMPS DOWN.....
back to the thread, Yoda and sidious would keep on fighting until the most powerful Jedi ever (NJO Luke) finally, after a long, amazing fight, kills Revan and help our little green friend to finish off the emperror (what i think....)