Gygax later made derogatory comments indicating he was pretty hostile to "thespian" play, and very much expected players to have more of a pawn stance to their characters, as you note re White Plume Mountain. This fits with the general Wargame approach of D&D pre the Hickman Revolution.
Yeah, there was definitely something there where it seemed that Gygax had a different idea of what the game was compared with what a lot of the players did.
I totally get both sides of the argument. Gygax was really (I think based upon what I’ve read over the years) looking at the published game as sort of a “tournament rules” where the “role” in role playing was more the idea of classes having a specific job and rewards were based upon how a player “kept in there lane”.
Which, if you’re looking at the game from the perspective of it being something done somewhat formally and competitively in focused groups, like a local bowling or softball league, this makes sense.
At the same time, there is a significant amount of anecdotal information that Gygax ran quite a “thespian” style of game in private. I think that many of us probably do as well.
I’m 45 and never have played in a tournament nor have I ever been to a convention, so the play style I developed was basically just the same as playing army in the woods with the neighborhood kids. It was just make believe with some guidelines to add some verisimilitude to our imaginations.
Now that I’m older, and if I had the opportunity to run a time limited convention game, I’d probably hew closer to a “crunchy” style and let the chips fall as they would. I don’t think that anyone at that setting would be looking particularly hard for character development.
On the other hand, in my basement with friends and family, if I wanted to play in this kind of a game, I’d probably just run HeroQuest instead of D&D.