Pfah!
Count Dooku wipes his old age-spotted ass with General Grievous's spare parts, after their thirty second duel. He then looks over to Yoda, who flies around Mace. Mace is an exceptional duelist, and I think is better than Dooku, so he'd last for a while. Eventually, though, Yoda would beat Mace down.
Then, Yoda and Count Dooku would eat apple pie, over Grievous's flaming remains.
If Mace and Grievous get lucky then Yoda wouldn't pwn Grievous but just beat him and Mace'd beat Dooku but then lose to Yoda. If the two got incredibly lucky then Mace'd beat Dooku before Yoda beat grievous and then thoegtehr they'd beat him.
But that would never happen. Nah, Yoda'd pwn Grievous even before Mace beat Dooku and then Yoda and Dooku'd win, no causilties.
Or else Yoda beats Mace, Dooku beats Grievous.