system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars] Vader seems like he hates Palpatine and wants to overthrow him. Why didn't he propose a team-up to Luke when they were both on Endor? Would the two of them together be able to take out Palpatine?
gpt
He tried that at Bespin but Luke was too resistive.  By the time ROTJ was going on, Palpatine was involved and Vader didn't want to be seen openly defying Palpatine as he could sense deception and would likely punish Vader for it. 

Vader doubted Luke would seek him out.  Palpatine said he would. Luke did that. Vader likely became concerned that his plan to turn Luke against Palpatine was exposed.  If Palpatine could see things even Vader couldn't that was not good.