Now, here's where I could very well be wrong, but I think my logic works out. To me, Shield of the Righteous is completely useless. I have not once been able to keep 100% uptime on SoR without Holy Vengeance being up. I understand that the damage reduction is awesome, but i'm used to being able to cast it on cd like back in wrath, not have to wait for 3 holy power to do so. To me, 1-2 attacks worth of PDR every 6 seconds and potentially blowing all of the heal on overhealing is not worth the self healing that I'm missing out on. Also note, I am using 34% as the healing modifier from SoR which is generous (as a haste-stacking tank I get about 31% in raid).
Let me break it down like this. I did a little chart on excel, and I'm going to ATTEMPT to link it here, if it doesn't show up i'm in the process of adding it in.

Now, the main thing that I'm looking at is holy power. That is the limiting factor to me in every situation. Therefore, SoR to me is a bottleneck that simply gives you a short burst of physical reduction that may or may not (I haven't spent the time to work it out) be more effective than the healing that you come out with. Assuming, as I do, that the healing is more effective than the physical reduction, this is what it looks like. As you increase stacks of SoR, healing per holy power goes down CONSIDERABLY, almost 40% with just 1 stack of SoR. Now, if you WERE using SoR, it would be ideal to use 3 holy power on WoG in order to maximize the percentage boost, but as WoG scales linearly to holy power, there is no reason to use more than 1 holy power on it when you aren't using SoR. The t16 4set bonus comes in at the end (markers 19-27), and does show an increase in efficiency, however its still not enough to match the healing efficiency of just WoG spamming. If there's a way to hit 100% uptime on SoR I'd really like to know.
