So basically your saying :

Dooku : Join me and together we will destroy the Sith!

Obi-Wan : Ok

Dooku : What?

Obi-Wan : You made a perfectly valid proposition, the Republic is corrupt and the Sith are behind it. I'll help you and your greedy bunch of Corporate movers and shakers to take over the Government with their droid armies and everything will be just the way we want it.

Dooku : You mock me.

Obi-Wan : Too right! You'd be mocking yourself if you had your head screwed on. If your evidence is worth throwing in with that lot and starting a war why not bring it to the Council?

Dooku : The Council? What are they going to do without support from the Senate?

Obi-Wan : I don't know, neither do you have you even tried? Or is being leader of your own Council too quick and easy for you to resist Count?

Dooku : It may be difficult to secure your release.