For me it is the question of whether I use my point of view vs. imaging the point of view of the protagonist character, who is not so knowledgeable, when making choices in the game. An example is letting Alfira die on the dark urge run, even though I knew of a way to save her, because my dark urge did not. That is not to say I don't metagame at all, I actually did on the run where I have tried to recruit Minthara, because I've had zero interest in destroying the grove.
I'd add at this point is that Larian has changed endings before. When I have played as Gale, it was even before they patched in the epilogue. At that point, if you chose to use the crown to obtain godhood, Gale would get obliterated by Mystra.
