system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars] What did Darth Sidious teach Darth Vader about the dark side?

Hey all, we know who the Emperor was as a person/as a Sith, but do any of you know what he taught Darth Vader about the dark side? From what I saw, it looked like Vader mostly taught himself while he was just the lapdog and enforcer for the Emperor. Do we know if Darth Vader, for example, had the ability to transfer his essence like the Emperor did in the Dark Empire?
gpt
Not sure about specifics but from the recent Canon book ***Tarkin***,we get this section
>“The two of them were in Sidious’s lair, a small rock-walled enclosure beneath the deepest of the Palace’s several sublevels that had once been an ancient Sith shrine. That the Jedi had raised their Temple over the shrine had for a thousand years been one of the most closely guarded secrets of those Sith Lords who had perpetuated and implemented the revenge strategy of the Jedi Order’s founders. Even the most 
>powerful of Dark Side Adepts believed that shrines of the sort existed only on Sith worlds remote from Coruscant, and even the most powerful of the Jedi believed that the power inherent in the shrine had been neutralized and successfully capped. In truth, that power had seeped upward and outward since its entombment, infiltrating the hallways and rooms above, and weakening the Jedi Order much as the Sith Masters themselves had secretly infiltrated the corridors of political power and toppled the Republic.

>Save for Sidious, no sentient being in close to five thousand years had set foot in the shrine. The room’s excavation and restoration had been carried out by machines under the supervision of 11-4D. Even Vader was unaware of the shrine’s existence. But it was here that they would one day work together the way Sidious and Plagueis had to coax from the dark side its final secrets. In the intervening years he had actually come to appreciate Plagueis for the planner and prophet he had been. Such perilous machinations required two Sith, one to serve as bait for the dark side, the other to be the vessel. Success would grant them the power to harness the full powers of the dark side, and allow them to rule for ten thousand years.”

So at bare minimum, this confirms that Palpatine was still planning to research/explore the dark side with Vader.