haste, on top of its natural benefits (i.e. reduced cast time, reduced globals (how is this still news? have you ever tried casting scorch?), reduced fireblast cd), also benefits from proccing kindling more often.
mastery on the other hand, is just a flat damage increase that spreads every 2 seconds (with the small caveat that you'll lose some ignite damage because your target dies before it finishes ticking). i figure combustion increasing our mastery also devalues it since that's how secondaries tend to work out.
this isn't "math" by any means, but it's just my personal explanation for why i think it's pretty intuitive that haste would pull ahead of mastery now that combustion is no longer a function of mastery.
edited: was wrong about phoenix reborn as proven below me.
Last edited by wombats23; 2016-08-20 at 10:15 PM.
Haste doesn't proc Phoenix Reborn more often - PR is a flat 10% chance per tick of ignite with a 3s ICD. Nothing about haste whatsoever since Ignite tick rate is unaffected by haste.
Frosted has posted the latest technology on the matter at Altered Time, consult the forum there. Crit is fantastic at entry raiding gear of 110, above intellect which makes me wonder if they'll do anything about it for the integrity of gear balance. Of course I don't expect those stat priorities to be definitely static so one could always find it important to simulate, especially if it's a special setup.
you're not factoring in hot streaks tho, which is the sole reason why mastery would pull ahead of haste, keep in mind, each hot streak doubles the gain of mastery, meaning that 1% mastery is 2% extra dmg from pyros and the vast majority of our dmg comes from instant pyros and ignite, meaning that most of our dmg is revolving around crit and mastery.
your arguements about haste are fine except for the kindling part, yes, it gives you more casts and potentially more combust but you'd need an obscene amount of haste to be able to actually get an extra combust from it within a boss fight.