This thread and all the other Beta/Preview threads for priests, will be going away fairly soon with the launch of WotLK imminent. For WotLK holy questions, constantius has a thread open for 3.0 which will remain so. (though I may rename it slightly)
OK, just to take this discussion away from CoH for a second, I was trying to think about the Greater Heal vs. Flash Heal spam thing the other day. The conventional wisdom is that GH spam is > FH spam in both HPM and HPS, and the only reason to FH spam is that GH spam is probably massive overhealing, and that FH spam is steadier, reducing the chance of "insta-gibbing" (not as much a factor if you have other healers, but nice).
However, unlike spellpower, there doesn't seem to be any manner in which Surge of Light and Holy Concentration are scaled with cast time. Don't Surge of Light and Holy Concentration have an equal chance to proc based on the crit of any spell?
In a 5 minute fight for example, you can cast 200 flash heals but only 120 Greater Heals and each of them has the same chance to crit, and proc a Surge of Light and/or Holy Concentration. Shouldn't there be some value of crit that for a long enough fight, Flash Heal spam will have better HPM than Greater Heal spam just by virtue of having more spells crit within the same period of time?
The model would have to assume that you optimally use HC procs for GH, and I have no idea how to account for Serendipity returns (which should be more of a factor in GH spam). Has anyone already looked at this, or is the required fight length simply too long for this to ever be a factor in real raid healing?
You essentially cast 1.6 Flash Heals for every Greater Heal. (Haste has no effect on this ratio btw) Modeling HPM and HPS is simple enough. You may want to consider that spamming FH gives you 1.6 times more chances to proc a crit effect. So, at 20% crit rate, over 100 GHs, you'll proc 20, but over the same amount of time, you cast 160 FHs, which procs you 32.
I would think that length of fight has nothing to do with it. No matter how long the fight is, you're casting 1.6 times as many FH's as you are GH's. You're therefore 1.6 times as likely to proc a crit spamming FH than GH. HOWEVER, by spamming FH, you certainly are losing HPM and HPS compared to GH.
I would think that you assume that proc'ing HC goes to GH. Someone with the numbers can look at the HPM and HPS of your free GH. Serendipity certainly screws up the calculations, though!