Some like only some references: I say that is picking-and-choosing. Some say the timing of a reference's creation matters: I say it only needs to be found in the final product. Some count in only some levels of granularity or detail: I say all game systems elide or omit detail.
This, then, implies that literally all games are simulationist, so long as
someone finds them to simulate something. I don't think that's very useful. That's why I consider the
origins of a mechanic, and contrast them against their
current usage, which absolutely can vary.
HP, levels, Vancian spellcasting, and a variety of other D&D mechanics were chosen specifically for their gamist attributes--or, at least, we can be as certain about this as we can about anything involving the creation of D&D, since its original creators are now dead. These mechanics have, in the time since, become ingrained in the overall...I dunno what you'd call it. Zeitgeist? Collective unconscious? of TTRPGs, and indeed gaming more widely. As a result, many people now take these things as
givens of TTRPG play, and thus consider them "simulationist" for that reason. However, I assert that those rough edges, which are often overlooked or denied by modern players (e.g. glossing over the very poorly grounded nature of discontinuous levels and
à la carte multiclassing, arguing that HP must in fact be meat points and not nebulous "you're still allowed to play" points)
are the original gamism shining through under the modern usage, and that it would in fact behoove many people who
want a simulationist game to sit down and really think about whether they want to keep such gamist elements.
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As for the previous poster who asserted that these things are impossible to mix together...I just don't see it, and having (re)read the assertions from the horse's mouth, I fundamentally disagree with the author. I
don't see a fundamental disconnect between "moments of drama" and "moments of well-defined conflict," because a conflict can be quite well-defined
without taking a side. E.g., if one has a conflict between two factions, one can have skirmishes between those factions be very well-defined things, embedded in the higher space of siding with one side, the other, both, or neither. Alternatively, you can have things like Dungeon World's
Undertake a Perilous Journey roll: the players clearly have a gamist goal (survive the journey without suffering excessive losses), but meeting that goal may require tough choices if the players do not roll very well. That's a narrative situation embedded in a larger game context, and yet
both things are tied together by invoking the
Undertake a Perilous Journey roll.
That sort of thing is what I mean by a single mechanic fulfilling multiple goals at the same time, either one embedded inside the other, or the two invoked sequentially, or the two invoked in distinct senses, but either way, a single mechanical action contributes to both. Gamism and simulationism are often (though not always) the hardest to reconcile on this front, because of what they "care about" so to speak, but even then they can work in tandem.