This is quite misleading in my view; you have based your percentage increase upon the assumption that you begin with zero spellpower. Using an equally arbitrary baseline of 4,000sp, the extra 100sp would only add 1.53% to your healing done/HPS.
I agree with your conclusion, but (as above) the reasoning seem faulty to me. The most important thing to keep in mind is that spellpower, crit, and haste all increase the value of each other as you gain more. Adding more spellpower makes haste more valuable. Adding haste makes spellpower more valuable - at least for a holy priest - as has been mentioned, disc priests are limited in the value they can extract from haste. There are definitely points at which a point of haste will be more valuable in terms of HPS than a point of spellpower for a holy priest.
Even with this in mind, I still support your conclusion that gemming for spellpower should be the preferred option. We only really get to have true freedom in choosing stats when we choose gems, since all available gear has a certain balance of stamina/intellect/spellpower, and then any two of spirit/crit/haste. When gemming, you can choose regen (i.e. intellect, possibly spirit), or throughput - so crit, haste, or spellpower. Of the three, only one increases the effectiveness of every part of every spell a priest casts - and thats spellpower.
You know what, you are right. I think I will remove that part of my original post and temporarily put something more vague there. I feel like this discussion really does need a comparison of haste and spell power so I really wanted to include at least something, even if flawed. However, I think what I have there now is just too flawed to really be of use, and is, like you say, misleading. I would ideally love to have something mathematical in there about the relative value of Spell Power, but I'm having trouble thinking of a way to come up with a more general comparison.
The idea that the three throughput stats are interdependent is something I should have been more explicit about.
And for your last point, perhaps the haste vs crit vs SP section should include a subsection specifically on gearing/gemming, stating the 5 possible gear combinations that Nicene posted earlier, as well as something on throughput versus longevity, and also your last point about the broad effectiveness of SP compared to crit and haste.
God damn it, Perl. The entire thing's in one single file that's almost 30,000 lines. A quarter of that is probably comments, but still. Yecchhhhh. You'd be better off starting from scratch.
Yeah, now that I look at the code maybe it would not be so simple to convert it for our uses. At least we know that the premise is sound and we can be justified in thinking this is a worthwhile approach.
We can definitely say things.
But compared to dps, which have a cycle and tend to spam it in most encounters (with some movement, or adds focus sometimes), we don't have it, and every encounter is a new theorycraft for us.
That doesn't mean that theorycraft has no value at all, but we shall be really careful with its assumptions before using it.
For example, Bobturkey's stats weighting and gear ranking is interesting, but because of its assumptions, I really prefer the "Take any iLVL increase" rule as holy priest, as long as the new gear doesn't have any hit (and if possible, MP5). I can find a fair use of all other stats. The distortion made by the strong assumptions (flash heal spam, MP5<->spellpower conversion) is in my mind greater than the difference in the final weighting.
Only exception is trinkets, where I use the difference to adapt to my current gear options and encounters. and where ilvl is sometimes meaningless (hello Solace).
I think we all agree that theorycrafting for healers is neither as simple nor as conclusive as theorycrafting for damage dealers. Like you said, everything varies by fight and assumptions like FH spam and mp5<->SP conversions lead to very questionable results, but to me that seems like the exact argument for
a tool like shaman_hep; it will provide values based on the your exact spell usage for a specific fight, not based on a series of questionable assumptions like FH spamming.
Like a Richelieu said previously, a tool like shaman_hep would not help very much with deciding what is the best healing strategy or spell usage for a particular encounter, but it would, somewhat conclusively, say exactly how to improve your gear to optimize your performance for that encounter and how you play during it. And that, despite its limitations, is very valuable.
It is possible with some work to achieve a similar result for Rawr using the Custom Role option.
I had never taken that close of a look at the custom role option, but now that I do it does appear to be somewhat of a halfway step between purely theoretical, assumption based theorycrafting and the combat log parser I am imagining. Being able to specify the exact fight length and how many of each heal you cast is nice, but it does miss some of the things shaman_hep does.
For instance, the crit rates for each type of spell (how often did Improved Flash Heal result in an extra crit?); overheal percentages, both crit and non-crit; how many spells that were cast were haste capped (1 sec GCD); how many times did your target die while you were in the act of casting a heal on him/her;
One could imagine a priest version of shaman_hep to also include things like: what percentage of SoL procs were used, expired, or overwritten; what percentage of FH casts were effected by BT haste (and PWS casts, and GH casts, etc.);
Those are only the things I could think of as I write this, I'm sure there are many more interesting things we could glean from such a combat log parser. The custom role aspect of Rawr is a nice stepping stone, but I think the possibilities are much larger.