Haste affects not only our casting speed, but it also affects our heal-over-time (HoT) spells…. by which it increases how frequent the ticks occur, and if you have enough Haste, it can add additional ticks of those spells. As Priests, we have a number of spells that are affected by this.
Renew (Disc/Holy)
Holy Word: Sanctuary (Holy)
Lightwell/Lightspring (Holy)
Hamlet, over at EJ, wrote a great write up on how to understand how this works, but we need to extrapolate this data and be sure we are rounding our numbers correctly. Binkenstein did a similar post at Totemspot. (in which he gives a headnod to some of the calculations/rounding to Hamlet and myself– and yes, I can confirm his calculations match mine). I have to give Bink some solid respect given how much work he did for all the HoT/HoT classes. So, Priests, lets take a look at our haste breakpoints for Mists of Pandaria!
One thing that is important to note, that in 5.0.4 and Mists of Pandaria, Hymn of Hope and Divine Hymn do NOT gain additional ticks with haste. They simply cast the spell faster. Now as far as what we’ll want to chase for breakpoints… well, I don’t like the term “chase”. Generally speaking, we’ll want to get our Renew breakpoint for the added throughput on Renew (ye old, 12.5% haste breakpoint)– provided we are casting it. Most 10 man and 5 man raiders will likely be doing so— 25 man raiders, may get additional mileage. More importantly, the breakpoint for Lightspring will be key. (and the adjacent Sanctuary breakpoint since its only 1 away) That said, it is important to know where these points are so you know when you are close and aren’t missing an easily attainable one. (Of course, provided you are using the spells that benefit from that breakpoint… meaning, if you are never casting Lightwell/Lightspring… getting that extra tick is not important).