Then it sounds like you are doing exactly what Blizzard is trying to get people to stop doing with this change. Please keep in mind that if you are upset about this change, it means that you are the kind of person targeted with this change. They want you to stop using PoH the way you've been using it.
Make no mistake. It is a nerf. It's supposed to be a nerf and it's supposed to change the way you play. It's supposed to discourage you from the way you currently do things (which was never intended), and force you into a situation where you try out other things. So rather than fighting it, and worrying about it, just respect it and live with it. PoH was given a Divine Aegis component on every cast as a band-aid. Blizzard is just taking away the band-aid and addressing the original problem that the band-aid covered up.
<-- 25man raider, IE the format that requires AoE healing the majority of every progression fight. Imagine trying to heal a fight like H. Garalon with only single target heals? While on a 10man that's not really a big deal, on 25man it's a HUGE deal.
I've been rolling PoH for 2 years ever since they added it in 4.0.6 if the fight was appropriate (high raid damage fights)
The only reason it's become a problem is because of the 30% -> 50% change in 5.0.5.
That being said, as I've said repeatedly, the problem isn't that they are nerfing our spells it is that we are getting no compensation for a complete change in play style.
If they want us to heal up after damage, why not make PoH competitive to do just that? Instead it's terribly weak and still gimped by it's party limitation. Why not change Discs PoH to smart heal when not under the influence of SS? The reason why in the past this has been shot down is because of the need to keep stacking DA... why not rid us of the party limitation and compensate for the changes done to our class.
10 man Disc while still the worst healer in 5.2, will be at least decent. 25man Disc is a different beast. The reason I spam PoH? It's because IT IS THE ONLY AOE HEAL I HAVE (that isn't on a long cooldown). Disc can't heal after damage, because other healers have much much better burst healing. By the time I've cast two PoH's, the raid is already at full (and thanks to smart healing, half of my PoH's have likely been overheal).
I did some heroic PTR testing last night and my throughput seemed fine. It does look like I'll be keeping my T14 4 piece for a while and there's going to be much higher usage of PW:S. Also, it's looking like Holy may come out ahead on fights requiring pure throughput, as Holy's output with the T15 2/4 piece is actually really good.
Overall, I'm really enjoying the new Disc play style involving weaving in Penance and PW:S/BT between the PoH casts.. Not having to spam PoH continuously is so much more fun.
10man Heroic testing. On 10man PW:S is a tremendous tool. on 25man it's pretty insignificant for anything other than emergency's. On 10man Penance cant hit 30% of the raid while on 25man a PoH is only 20% of the raid.
Again <--- 25man raider. 10mans are a completely different beast.