Palpatine's accolades

Taken from a Google+ discussion:
To anyone reading this, not just to the two people above: I have been thinking on this, and I don't think the aforementioned accolade should be taken at face value. For one, it's practically identical to the "Yoda is the most powerful Jedi in history" which we KNOW to be false, at least to some extent (GM!Luke anyone?).
Now, you might say "Well, Yoda was the most powerful Jedi up to his time, it does say in "history" after all, with Luke coming afterwards". However, the same excuse would apply to Sidious, allowing Krayt or Caedus to usurp his position (Although I think Krayt at least has quite a ways to go before that). Plus, a majority of Sidious's accolades are along the lines of "best" or greatest" Sith in history, which is NOT the same as "Most Powerful" (For example, I would say Master Fay is the greatest Jedi in history, but certainly not the most combativly viable).
And even "most powerful" does not guarantee a win. I think we can all agree that Vitiate was one of the most powerful Sith in history, most certainly of his day. However, I think we can also all agree he was borderline useless in a one on one fight compared to the likes of Bane or Kun.
The accolade "Greatest whatever ever" could also only apply to that specific version of the group. For example, "Yoda is the greatest member of the old, post-russan or tcw* (whichever) Jedi order, but Luke is the greatest of the New Jedi Order. Following from that, Sidious is "merely" the most powerful member of the Order of Sith Lords (Better known as the Rule of Two).
It should also be noted that the accolade "Most powerful Sith in history" fits MUCH better with Dark Empire era Palpatine than ROTS Sidious. Not only did he have 20+ years of doing almost nothing but advancing his skill with the Dark Side, but he also demonstrated a wide host of abilities (Destroying entire fleets, draining entire planets of life, granting connections to the Force, etc) that were above and beyond the scope of almost any other Sith Lord, including his younger self.