Looking For Stunning Advice, Morimar Delve 5NM

I agree the biggest part of apajamas ii devotion comes from the time when neither atinian nor the now widely common +magic accuracy skill. In that time, apajamas ii was the absolute top staff, as no staff even came near its macc, even less its recast.
I dont know if -% recast fall in category of fast cast. I dont know the right equation, but just looking the diferent nouns and diferent effects (fc is cast and recast, and this staff is just recast), i would guess those are calculated separately.
I also agree apajamas became situational nowaday. Thats because the stupidly large interval between dangerous move of mega boss. Once you hit the interval as the same of party overall stun recast, and thats easy to do nowaday (like 15 secs per sch if x2, 30 secs if you can keep alacrity full time, possible of your dds are good enough to kill boss in less than 5 mins), any haste, fast cast, -recast is wasted.
Just to be fair, apajamas and atinian is a trade off of 133 macc for 14% recast. But just want to point that 133 macc isnt that great as it seems. I dont know how exactly boss resist mechnic works, but if i would bet in something, i would say its exponential, because once you miss one stun, you can even hit the next, but then every stun will miss, meaning after next resist, meva is a lot higher than current mage macc. In real situation, +133 macc (after you have an good amount already) dont mean like 20 or 30 plus mins till stun wall. Just barely 1 or 2 mins of stuns. And thats after 8 mins of stuns with apajamas.
We are at a point (in delve at least) where apajamas isnt necessary anymore, nor even a high macc staff, and honestly, not even schs (as i think a rdm can reach that minimum recast without alacrity). But what will decide your really need is the party setups and quality of your players.

i think it's a personal preference. In a normal delve setup it's unlikely that there isn't a geo present for languor and focus (languor also helps your whm to stick debuffs on nms so it's nice to have anyway). Any sch who have shark/bee gear can sufficiently land stun until resist wall hit, whether they use atinan or apa II. There isn't really a resist problem or a recast problem if you're adequately geared. How you wish to jiggle your gear to get that recast down with decent macc is entirely up to you.

Apa 2 has the benefit of recovering slacky mages not hasting you or marching you until it wears/you shouting at them, so with apa2 and alacrity you can recover your recast without staring at a move that you could've stunned if buffs were up.

Atinan has the benefit of maybe landing a few more stuns before stun wall hits (if you get to that point you're prolly not going to win anyway, but hey!). That being said, any decent scholar who devoted time and effort to get a apa2 would probably have atinan or a ilvl 117+ weapon on them to switch to if it's needed.

hahaha

Recast reduction is a matter of sufficiency. If your recast reduction is gimp before entertaining the use of Apajamas II, Apajamas II may be needed. If it isn't gimp, there is no marginal benefit from Apajamas II for reducing recast. You're either under the maximum recast time necessary or you're not. Any excess doesn't matter. (Of course what is "necessary" depends on your appetite for risk and/or inefficiency, like this ***even matters these days. LOLdelve)

Magic accuracy benefits of ilevel weapons are not about the stun wall, but about eliminating the need for Focus and Languor as the opportunity costs of using Focus and/or Languor are other GEO debuffs that can help kill ***faster.

You will get resists with Apajamas II before the stun wall vs Atinian for example; gear alone is not enough for Apajamas II. (Granted I have not collected data on frequency of resists but why bother when you can avoid the pre-wall resist issue altogether.) With ilevel weapon magic accuracy, enfeeblers should not be so gimp these days as to rely on Focus/Languor anyway (ilevel weapon magic accuracy >>> Focus and Languor combined, probably).

Apajamas II might help with gimp Marches (like +2) if you're stunning by yourself (this is the ONLY reason, albeit a stupid one, that I even got Apajamas II for Tojil) but doesn't help if Marches drop outright (or Haste spell if the Marches are gimp), at which point Alacrity covers this (Apajamas II is irrelevant with Alacrity). And as I said already if there's another stunner Apajamas II recast reduction will be superfluous even with mediocre magic haste.

So basically you can choose Apajamas II if your recast is gimp or Atinian if you have GEOs doing other buffs/debuffs that will help speed up a run.

Advocating that people get Apajamas II today (post magic accuracy adjustment) solely as a marker of "competence" is a stupid argument.