Obviously, for the Dark Sun purist, neither solution is satisfactory, since the point of separating magic and psionics is to keep continuity with the original Dark Sun story. Casting a spell and manifesting a power of the way should feep different within the game. And yet the most powerful creatures on Athas combine spellcasting with psionics.
This is a companion discussion topic for the original entry at http://athas.org/articles/Athasian-Magic-and-Psionics-are-Related