Note that I didn’t say “confusing”, I said “confused” 
The game doesn’t really know what it wants to be. Which may or may not be pardonable due to the fact that it originated before the whole GNS thing was a widely acknowledged thing 
But either way, the fact remains that 3.finder is neither very well playable in full Simulationism mode, nor in full Gamism mode.
For the former, things as basic as hitpoints (no “pain” penalties for being down to 5% of my life force?? No lasting scars and cripplings?? Why do HP increase like crazy over the levels?? etc…) make no sense and will break the “immersion” and “verisimilitude” (a nice term just to avoid saying “realism” 
) that Simulationist players and GM like to go for.
For the latter, it sort of works (the game admittedly caters to Gamist “Step On Up to the Challenge” agendas more than to any other GNS mode). But still, play tends to get bogged down in a large number of rules apparently there mainly to “simulate realism”, and having nothing to do with challenging the players’ tactical prowess or dice-rolling luck (which would be core tenets of Gamism, though).
Sure. But that’s the Realist speaking here. That’s Simulationism.
Which isn’t a bad thing, it just is. (Which is why I included it under the examples for Simulationist rules, there)
[That I think the Simulationist approach is fundamentally flawed and rarely leads to functional play, does not intrinsically matter for this debate right now, but may hereby be mentioned anyways]
A full Gamist would probably prefer to roll for the jump according to how challenging the chasm or cliff (or whatever) is supposed to be to the party. If it is not supposed to pose a real challenge at all, why not just narrate the whole party breaking out their climbing gear and making it over eventually? Why bother to have everyone roll against a DC of 15, when it is reasonably clear that we’ll end up making it anyways, that it will not noticably deplete us of resources, and will not cost us any HP?
Just because it’s “realistic”? To the full Gamist player, that would not be a meaningful criterium.
If they see a chasm ahead, they are more likely to expect the GM posing a difficult challenge before them, one that they have to get creative, and use their resources at best they can to solve it. DC 15 chasms should not exist for such a player, from a certain level onwards. Or as soon as at least one or two members of the party have high enough Climb skills to be able and help everyone else get over it.
It would just be a waste of time, on the way to the next interesting challenge…
The Narrativist, finally, would want the DC of their chasms and cliffs to “serve the needs of the story”. Because that’s what they’re here for, an exciting story, a great adventure.
If there is [something] to be jumped over, the Narrativist GM would judge the DC for doing that according to dramatic and cineastic criteria. Is this an “establishing test” for the characters, early on in the 1st act, merely meant to showcase their respective strengths and weaknesses? Make it DC 10, perhaps.
Is this an “intermediary challenge”, somehwere in the 2nd act, meant to perhaps slow them down, or even force them to double back and seek another way forward? Perhaps to test their resolve, and/or inventiveness? A DC of anywhere between 15 and 25 might or might not be appropriate… (depending on the characters, the story, the situation, etc.)
But what if we are deep in the 3rd act, close to the Big Bad Evil Guy? Throw a chasm at the party that will stiffle their breath! An abyss for poets to compose sonnets about! Let us see them cross this gaping maw of hellish oblivion, or despair!
(Or, well, you know, just narrate “the caves are full of cliffs and chasms, but you navigate through them and over them expertly and confidently, striding only towards your ultimate goal…” and let it be good with that - all depending on the needs of the story, and your own sense of drama and that of your group)
Note that the Narrativist approach may never even mention “distances in feet and yards” (except maybe for color, as in “the gap is at least 20 meters wide, but your Monk jumps over it souverainly and unfazed”)
The Simulationist will likely begin with distances measured in [whatever increment]. (Because that is important to determine DC, because “that is how difficult it would be”, right?)
And the Gamist approach thinks first about the toughness of the challenge that should be posed by the [chasm or whatever], and then resort to feet, yards and squares, while settling for a desired DC for the jump.
Note, that none of these playstyles usually show up as “purestrain” as I described them here Virtually all Actual Play features mixtures of the playstyles of course.
Also, many GMs may not even consciously be aware how and why they determine DC, distances in yards, and various dramatic considerations, while actually writing an adventure.
But it bears thinking about, imho.
