Well, if they weren't already too old games i'd suggest you to give them a try and see by yourself. ^^ It's like i said...as soon as the mechanics aren't there just "to be there" (like the current repair system, that has no purpose other than gil sink) it does is a valid idea. I do think all basic needs have a space in MMOs...so what if you will need a "poo break" every now and then...at BTN quest you need to harvest yarzon crap...why not just using your own? =P
IMO these concepts don't fit Yoshida's MMO though...he envisioned a pure battle-related, overly simplified, retard-friendly game...for such kind of game would be much easier just giving players "godmode" items and automated play options so the players won't even need to play the game...it would play by itself.
But when a game proposes the concept of being heavily immersive and realistic, like the original FFXIV, these concepts are totally valid.
[yeah, yeah...now we can have a crybaby pause so @sskisser fanboys can say that that was why FFXIV failed]
Now back on-topic...i do think these kind of mechanics are valid...you see, some fatigue system (not talking about surplus) would be very useful to turn long battles more strategic...having people managing their effort instead of the NM "enraging" after 30 minutes would be cool. Getting hurt would be cool, weapons breaking would be cool...
But this all is about what a player want to see in a game. I like immersion and realism...you don't. This is why i've been bothering SE to have the old FFXIV back as spin-off...this way they could cover both playerbase preferences AND have them both focus on the concepts they were built under...Yoshida's FFXIV has no space for surplus, fatigue, action-oriented content, gear management, housing, etc. With both games he should just focus on what the game is meant to be offering...constant frustration, e-peen focus and flawed content...errr...i mean...extremely challenging battle-oriented content with spoils that make them worth doing. =P