The game developers have said that Vader simply didn't plan on attempting to overthrow Palpatine at this time. He intended to do it eventually, but not yet. Galen was not his "chosen one" (pardon the pun). He planned on doing it at the very beginning of his apprenticeship when he was ultra powerful, but those plans were foiled when his injuries left him but a shell of what he once was, or had the potential to become. He put those plans on hold, at least for a while (if not indefinitely) until he found the perfect potential apprentice to help resurrect this plan: Luke.
Though your theory could very well be correct. I suppose there was also Lumiya, as well as others that we would be remiss to forget about when considering all of this. What roles, if any, did all of them play in Vader's plan to usurp the mantle of Sith Master and galactic Emperor?
Originally Posted by a silly noob
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