The question of how Bill Slavicsek came to his conclusion about Borys being the creator of the metamorphosis process is an interesting one. The most clear inference that I and many others made is that Slavicsek simply made a mistake. However, Slavicsek’s mistakes are our canon at the end of the day.
The champion vs dragon vs sorcerer monarch is one of the most vicious debates in Dark Sun circles, and has the least impact on the game as it is played itself. To my mind, ‘shadow wizards’ drawing power from the Black, ‘necromancer’ drawing power from the Gray, and ‘ceruleans’ drawing power from the Cerulean Storm are the far more important question. No concept has been more deleterious to the Dark Sun setting than the special energy sources introduced in Defilers and Preservers: The Wizards of Athas. Ironically, defilers and preservers becomes a misnomer, because under these new rules defiling and preserving henceforth becoming a meaningless concept because of the special energy sources. Thereafter, every PC, without exception, was either a shadow wizard, cerulean, or necromancer. At this stage, preservers were defiler lite.
Needless to say, none of these special energy sources exist in my conception of the Dark Sun setting. I realize this is a fantasy setting, but a little realism goes a long way.
That is very clearly the case. Either Slavicsek misinterpreted the details in the Prism Pentad, or he innovated. @phaaf_glien and I raised this issue on the old Wizards forums. I remember Kamelion there too, saying much as he is saying now. Its a very old and contentious debate, but as I mention above, not even close to the most important one.