Ah, yes - how he knows. I've actually moved this scene to after Palpatine's reveal. Though it's hard to see in just one unfinished scene, I want to depict that Anakin is already sort of in-league with Palpatine's before he "officially" turns.

Last night I moved the "plot to destroy the Jedi" line to earlier in the scene, and it seems a lot less like he's delivering an obvious line.

I've also intercut some more Anakin musings, as well as Palpatine communicating to him through the Force. It both further justifies Anakin's action, and pads the scene out so it doesn't feel so rushed. I think it works pretty well, and I'll have an updated clip up fairly soon.