Evidence of Palpatine's Power Growth: TPM to RotJ.
This is a thread in which to discuss and present evidence for Sidious' power growth from the end of The Phantom Menance (i.e. post-Plagueis death), through to his confrontation with Yoda in Revenge of the Sith to the moments before his death in Return of the Jedi.
It's generally assumed that over the course of this thirty year period, Sidious grew more powerful and knowledgeable in the Force. But what sources/reasoning can be presented to define the extent and nature of this increment? And what gap do you think exists between his incarnations?