OK, that's fair enough. Though I'm not sure that this alters the situation, especially since we were using the same definition of "synthesis".
I maintain that great storytelling is not the synthesis of good storytelling and powergaming. It is a subset of the former, not a reconciliation of the former with the latter by showing a new possibility or idea.
In fact, I maintain that powergaming and storytelling are distinct and pretty much independent objectives. An admittedly crude analogy (appropriately enough, from gaming) would be the Lawful-Chaotic axis versus the Good-Evil axis. For example, given a choice between LE and CG, the character motivated only by good chooses the latter, thinking the former anathema, while the one motivated by only by law chooses the former, thinking the latter anathema. In other situations (LG vs CE) their views would be in accord. The question of whether the two coincide is entirely situational.