Luke did defeat DE sidious but he had help so what would have happend if he had no help, when it was him against the old emperor he almost died, and he got TOTALLY owned by the DE emperor, and the DE emperor had new powers, both there lighthing skills are equal or comparable are they not, DE sidious cant open a black hole but his force storm is kinda like one aint it, jacen solo can heal the dead or whatever but sidious learned to improvise with his body switching power, im not saying sidious wins, im just saying he's REALLY powerful dude, even before he learned all these new powers, and with a younge body he was to much for luke wasnt he, did he cut off sidious hand before or after he started decaying.