Maybe I'm missing your point here, but it seems to me that - at least in 4e and 5e D&D - the trade off between a two-handed weapon (more damage) vs one-handed weapon and shield (more defence) is expected to be a meaningful one, where neither option is strictly superior to the other.
So choosing to have a two-handed sword or axe, vs a one-handed longsword or battleaxe + shield, is not imposing a mechanical burden on your PC.
Whereas if you are a barbarian who chooses a quarterstaff as your two-handed weapon (d8 rather than d12 for the axe) then you have imposed a mechanical burden on your PC.
My suggestion was that, in the latter sort of case (previously I canvassed a monk who renounces weapons, or a fighter who wields only a shortsword), we could add a Vow slot to the personality mechanics ("I vow never to use a weapon", "I vow to wield only my father's shortsword", maybe the barbarian admires druids and says "I vow never to wield tools made of metal"). The player would then get Inspiration for upholding the vow, which would counter-act the mechanical penalty to damage.
As I already said, I haven't done the maths in any serious way - it's just an example of the sort of thing that can be done within a 5e-ish context. I don't think the logic of it is that puzzling.
I never said your logic was puzzling, though I am asking for you to further explain your reasoning in the context of 5e...
To clarify...I'm asking why, the monk foregoing the ability to use other weapons and with the unarmed attack being one of a monk's viable options (that does in fact increase in damage as he goes up in level and cannot be disarmed, is naturally hidden etc.) why he should get some kind of advantage for that because of his "vow" but if I am in turn limiting myself to two-handed weapons, when I have a much wider repertoire I could use (the same thing our hypothetical monk is doing) you don't see this as this as a disadvantage... why is that??
In other words...
1. what is your original logic behind the fact that something like the vow for inspiration is even necessary.
2. Where does the line get drawn once you do something like that? What if I limit myself to 1-handed weapons... or blunt weapons or... well I think you get the point. What is the criteria where one is allowed to have thus type of vow and another isn't in 5e.
I don't know what "book" you're referring to. Do you mean the HeroQuest revised rulebook? Or the FATE core rulebook?
None specifically but I've played both HeroQuest and FATE and unsurprisingly enough they are similar enough in the area of free-form descriptors that I don't think the particulars are all that relevant for the point I am trying to make.
Upthread (post 605), you said "I don't agree that the systems themselves are particularly good at representing a wide variety of character types mechanically because the games like HeroQuest, Fate, etc essentially eliminate there being an actual choice with weight." I replied by saying that "The weight of choice is moved from mechanical minutiae to fiction and framing." Now you are asking whether there is a mechanical difference between Dagger Dervish and Disciplined Sword Saint.
If you go back and read the post you are referencing, I am quite clear in that I am talking about mechanical weight (though you wouldn't know it by the sentence you chose to selectively pick without context)...
To repeat myself: the difference or the weight is located in the fiction and the framing. If it never matters in the fiction of your game that you are a Dagger Dervish rather than a Disciplined Sword Saint, then you are correct (tautologically correct, I think) that nothing will turn on which descriptor a player writes on the sheet.
I never claimed it wasn't located in the fiction... go back and read my posts, they are about mechanical weight.
Now what I did say about weight in the fiction was that the game in and of itself doesn't give any weight to that either, instead the heavy lifting of whether a particular descriptor has weight in the fiction is shouldered by either the GM and/or the play group consensus...
Just off the top of my head, here are some circumstances in which the choice of descriptor might matter in a practical or procedural way: you are fighting in confined quarters; you are in a combat where you and your opponent(s) start outside of arm's reach; you want to use your weapon to reach under a couch/vehicle/low-ish verandah/etc to knock out some item that has fallen underneath it; you are trying to sneak into somewhere while armed; you are applying for a job with the militia; you are trying to do an impressive dance.
Emphasis mine... since you used the term "might"...what determines if it does or doesn't matter? Do FATE or HeroQuest give hard and fast rules for determining the fictional weight of descriptors? Or is it basically up to the group as I said earlier?
Here are some circumstances in which it might matter in a more dramatic way: you are trying to become master of the dojo; you have to fight a duel over a point of honour; you arrive at the Temple of the Moon and beseech the high priest for aid.
Again that word might... how does this work for someone who wants abilities that allow him or her to affect or impact the fiction without having to relyy on the GM/ player groups consent? Honestly this seems like the exact opposite of what the OP is talking about.
As for what is being "ruled on": in these games (I can't comment so much on FATE, which I don't know as well, but I think it is broadly similar in this respect to HeroWars/Quest, Maelstrom Storytelling, etc) the GM has to adjudicate fictional positioning to (i) establish that action declarations are permitted (eg if my PC is across the road from yours as a procession is passing by, I probably can't declare an attack against your PC using Dagger Dervish), and (ii) to impose any modifiers on the raw check that might be required (eg if my dagger-wielding PC has to close on your sword-saint PC across an open field, you will have the advantage due to weapon length).
We're still using words like probably... That again makes me feel as if this stuff is kind of up in the air until the GM or the group makes a ruling. You say Dagger Devrish probably couldn't be used to attack from across the road as a procession goes by.... but why not? I could see part of Dagger Devrish being a wild whirlwind like attack of multiple throwing daggers that whizz and whip through the unaware participants in the procession... but another GM might find that unacceptable. That's what I mean when I say the weight is pushed to the participants. From the above you (the GM) or the group are actually determining when and if my descriptors are effective... is that correct? If so what weight are the actual rules determining when it comes to fiction?
This doesn't seem to me to be wildly different from what a 5e GM has to do in adjudicating non-combat action declarations (which requires determining if success is possible, if so if it is uncertain, if so what the DC is, and also whether or not a given skill is applicable). This is why I was puzzled by your suggestion that adjudicating action declarations in these games has some sort of problematic feature that D&D lacks.
I disagree... When I use daggers in 5e I know they can be thrown, I know how far, I know how much damage they do. There are rules for attacking through cover (the procession) if I want to throw them at a sword saint on the other side of it. For skills there are descriptions (under ability checks) that set the baseline for what they should encompass and for some actions under them (such as swimming, climbing, spotting something, etc.) hard rules... there are none for free-form descriptors. IMO that's the difference I am pointing too when I say in one (5e) I am adjudicating in the other (FATE, HeroQuest) I am creating the "rules" for what descriptors can accomplish, whole cloth.
