light and heavy attack WERE based on stamina up until the last beta phase... but they seem to have changed this for release (no notification of this change have been done but after testing it I can confirm that even light and heavy attack are affected by max magika now)

this is one of many example of things that were pretty strange and got fixed with the transition from beta to release...

other example are:
damage shields; during beta they were not affected by armor or blocking but are now effected by those... so the same damage shield will last longer on a tank blocking hit than what it would last on a paper wearing non blocking character

Equilibrium; during beta (and early release) it applied a self debuff that almost nullified self healing for a few second after cast, this has now been removed and you get full benefit of your own healing right after casting it


so... while I still apreciate the effort of many beta tester that spent their time (especialy during the last beta phases) to explain game mechanics, their conclusion may not be true anymore