Originally Posted by
Koor
It's slightly less than quadratically, but basically it's correct if we look at HPET: Baseline riptide has 250% sp direct heal, and 300% hot, therefore its HPET with a GCD of 1.5 seconds is (250+300)/1.5 = 366.66. With 25% haste, we'll have HPET = (300*1.25+250)/(1.5/1.25) = 625/1.2 = 520.83. Therefore the scaling in HPET is 520.83/366.66 = 1.42, significantly more than 1.25 (but slightly less than 1.25*1.25 = 1.56).
But is HPET the correct metric to look at? Ideally we want to use HPS to derive stat weights, not HPET. A druid can convert the HPET benefit into HPS since rejuv can be spammed, but we are locked with the 6 seconds riptide cooldown. It's not relevant to the HPET of riptide, but it's very much relevant to the HPS we can gain out of more haste. Yes, 25% haste gained us 0.3 seconds. Out of 1.5 seconds it looks like much, but in contrast to a druid, we can only benefit from those 0.3 seconds gain once every 6 seconds, not every 1.5 seconds like a druid, so the HPS benefit from haste is four times less than the HPET numbers would suggest.