-Anakin and Obi-Wan approach Dooku.
-"You're gonna pay for all the Jedi you killed today Dooku," or a similar line.
-New Dooku line in wideshot: "Indeed" from Clone Wars (I know it's not Christopher Lee but it sounds exactly like him in that instance). He knows the Jedi are no match for him, and is amused by Anakin's statement.
-"We'll take him together."
-Dooku ignites saber and salutes Jedi (from begining of Yoda duel).
Obi-Wan charges at Dooku, they fight. All dialogue is cut.
-Anakin watches not knowing how or when to intervene (possibly coming from cropping full screen DVD, zooming in on Anakin and slowing down footage with duel soundeffects in background).
-Dooku cuts Obi-Wan, says to Anakin, "As you can see my Jedi powers are far beyond yours." (not sure how to accomplish this exchange) "Abilities" or "skills" would be a preferable term to plug into that line though. Heck, maybe even, "As you can see, my skills with a lightsaber are far beyond yours," or any combination of unused lines from the Yoda duel.
-Dooku raises saber for the kill. No twirling or hesitation, or CGI jumping Anakin. His saber comes out of nowhere to save Obi-Wan.
-"Brave of you boy. I would have thought you'd had learned your lesson." "I am a slow learner." Dooku is referring to making quick work of Obi-Wan.
-Duel continues, Anakin's second saber is cut away by Dooku.
-CUT to Padme recovered in the desert.
-CUT back to duel, Anakin and Dooku fighting in shadow.
-TM's plans from then on: Yoda, etc. Padme arrives with clones to shoot at Dooku's ship and embrace Anakin.
Not perfect, but a rough outline of a possible scenario.
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EDIT: I moved Dooku turning on his saber to inbetween Obi-Wan's line and his action. This way the cut isn't to choppy.