Originally posted by Man of Christ
palp had become decrepit too
No, he became more powerful as a result of studying the force to a greater extent. For example, he could mindwipe billions of people to prevent them from attaining knowledge of the Lusankya, he killed dozens of stormtroopers with his force lightning, and disintergrated people with one-handed lightning.
Oh, and Mace beat Sidious thanks to Vaapad. He won't have that advantage against Obi-Wan, who is a lightsider. (But he still curbstomps him, being faster, more physically conditioned, and an overall superior swordsman)