Quote Originally Posted by Ultimatecalibur View Post
12s is actually incredibly loose for a 5 gcd burst window even with a 2.5s spell gcd. 15s would just be overkill.
It's not loose by any means. If you recall SB Requiescat (lvl 70) you actually have only half a second margin for errors. Sure, the game treats uninterupted casts as "casted" like half a second before you have actually finished "casting". But if you deal with a ping of 50-200 ms, this 0.5-1s is needed! 2.5s cast spell wouldn't finish before Requiescast drops, unless you are really lucky and/or play right beside the servers.

I guess the 12s window is an old restriction of pre-ShB where MP wasn't fixed on 10k, and you had other ways of generating more MP, e.g. Refresh from BRD/MCH or an Ewer card. A longer duration would've increased the potency of a possible 6th HS. Also, HS was the hardest hitting action in PLDs toolkit at that time iirc.

I agree 15s would be overkill. Any duration increase - if at all - should range between 0.5s and 1s (so either sneak-buff it to 12.5s or 13s). Honestly, with IR and DelIRium having actual ~10.74s durations despite the displayed 10s in their tooltips, Requiescat could get the same treatment. (It's already the origin for IR, so that would close the circle.)