What do you mean or what do you have in mind, when you use or read the word "gamist" in a discussion? I think the term is used quite a lot, but not everybody means the same thing...
These days, I just treat it as a cipher - it doesn't mean anything unless I know that the person using it means it in a specific way (and, even then, the meaning might not lend the term much value).
As to using it, I try not to, these days. Partly this is because it has no well defined or accepted meaning, partly it is because the meaning I find most useful (the GNS one) seems to stir up unrelated animosity. If I'm going to be required to be held accountable for every last act and utterance of Ron Edwards - his emails, his forum posts and any illegitimate children he may have fathered - just because I say that I find GNS to give useful definitions to aims or foci adopted in RPG play, I'd rather just avoid the issue.
Personally with the word "gamist" I mean mostly the attitude of reasoning in terms of codified rules, rather than in terms of what those rules originally represented.
I think this definition is problematic in the extreme - I'll explain why below. But here I'll just say that, when playing an RPG, one either:
a) reasons about the game world according to ones own particular understanding of the "real" world, assuming that the game world conforms to what is true or feasible there (maybe with an "except where otherwise stated in the game book" inserted, here), or
b) reasons about the game world according to the "reality" of the game world itself, as shared by the gaming group.
Both of these
are the "rules", as I see things. The rules might or might not be written down, but the function of them is to act as a communication between the players - including the GM - about how the game (world) works. If the written mechanics aren't what is performing this function, then they are (de facto) not the "rules" in use. Whatever defines the game world to the group who are playing? That is what "the rules" are.
Which is where the definition of "gamist" as "only looking at the rules" starts to run into problems...
So for example, for me a "gamist" thing to do is to unconsciously forget or consciously refusing to acknowlege what a certain PC's ability/action represents and instead just focusing on what the written rule allows or disallows explicitly, and what it doesn't explicitly forbid, and perhaps ignoring an eventual mismatch with the non-rules part of the description.
This immediately tells me that you are, by default, thinking of a roleplaying game as having "rules" that are not what is written down in the game system.
I don't, necessarily, have a great problem with this - even though it tends to diminish player agency (just because, if "the group consesnsus" is taken to be "how the game world works", it's very common for the GM's view to be given de-facto primacy). It is extremely demanding in terms of communication to get to a point where everyone at the table has some reasonable idea of how the game world
does work, though.
And, there are specific issues:
To give a more concrete example, let's say the rules include a special action that represents widely swinging your weapon to catch multiple targets at once, but then the rule forgets to explicitly mention "in a line" or "one after the other". A "gamist" attitude would be to ignore the fluff (i.e. the description of what the rules represent) and focus on the crunch (i.e. the description of the mechanics, how using the action works) and declare that it's possible to use this action to strike targets in any order (e.g. in directions NE, SW, NW, SE).
This illustrates nicely, I think, the issue with having "the game world works just like the real world works, but with excpetions noted in the game book".
Everyone thinks the "real" world works differently; especially when you add in some throwaway like "in medieval times"...
The situation described here obviously strikes you very differently from the way it strikes me. To me, based on a reasonable understanding of Western martial arts gleaned over the last 5-10 years, "a special action that represents widely swinging your weapon to catch multiple targets at once" strikes me in several ways:
1) as a good way to commit suicide, if it means "just whirl the weapon at arms length in a big arc while in melee combat". This will give
so many openings to your enemies it just isn't funny.
2) possibly feasible, if done as a combination move designed to protect while simultaneously delivering several blows. These blows would by no means have to be against enemies "in a line" - a wide, horizontal arc is possibly the worst vector for such an attack. More plausible would be some sort of vertical swing, maybe combined with using several parts of the weapon to make blows as well as provide shielding. An axe with a point extending from the handle top, for example, might be used to stab with the point prior to an anterior vertical swing inside your own shield, which is itself used to thrust (making an opening) at an enemy on the opposite side of you while simultaneously shielding your axe hand, allowing the axe's swing to come up into the opening (strike two) and continue up and around as you dodge and twist - bringing the axe's downward swing onto a third target.
So - you see the targets all being in a line adjacent to one another as a prerequisite for such an attack, but I see it as actually making a coherent attack sequence
harder (becuase you will need to somehow get all those axe moves to "flow" into one another while all striking in the same direction, quite against the way the momentum of the axe will work).
Who has the right interpretation? It doesn't actually matter. If you want weapon "swings" to work that way in your fantasy world but I want them to work my way in my fantasy world, we're all good!
But, can you see that if either of us "advertised" our own fantasy world as being "based on the real world" and had the other of us playing in it, our GM calls on what is "realistic" might very easily confuse and offend the other of us?
What's your take on the word "gamist"?
It's a word with several possible meanings, some of which can be quite useful, but the lack of any consensus on its meaning makes it essentially useless in discussion.
This means that there are some useful concepts that have to be re-defined and explained every time they are discussed, but since it's the function of "jargon" to eliminate this need, and there are many folk about who fight tirelessly against jargon, it's what we're stuck with.