So, this could be used to support any of these arguements.
And it just so happens that it could support one who believes Palpatine manipulated the situation. It is easily within the realm of his abilities. As a manipulator, he is peerless, and played Mace like a fiddle for years.
He could just as easily have done it again.
I actually hate that part, as with the Tusken echo on the Hand. Its him remembering it, not Palpsy speaking to him.
Palpatine's voiceover was never spoken during Anakin's confrontation with Palpatine in his office, earlier.
But really, why risk damaged goods? It would have been much easier to do it many other ways. [/B]
Unfortunately, the entire thing came down to somewhat of a risk. There was always the possibility that Anakin could have simply rejected him in the first place. He took a risk by letting Anakin kill Count Dooku. Had Anakin not submitted, he would've been without an apprentice. The same applies here.
When Palpatine finally confessed his identity, Anakin did not immediately accept, and instead said he would turn Palpatine over to the Council.
Perhaps Palpatine thought, by contacting him and pulling him back to the office, he could force Anakin's hand. If he attacked Windu and his team, then it would shut the Jedi off from Anakin. They would no longer see him as an ally, almost forcing him to choose Palpatine instead.
That Palpatine dominated the fight with Windu for half of the time, then the second half being a stalemate, and then being disarmed seconds before Anakin arrived, seems a little fishy.