First off... no i didn't read every single post in this thread, but i just want to make a quick post.
I used to play a holy paladin (wasn't for long but was during the "OMG INTEL STACK" stage) and i understand the benefits of intel stacking. But i think the days where you stack int and spam HL are over, and people who are clinging onto that idea are a little short sighted and don't want to change their ways because it actually requires a bit of work on their gear and how they actually play.
Me and my guild currently only do 10man content as we find it more fun, and one of our 2-3 healers is a holy paladin (who happens to be my GM). He used to be a crit and int whore like i used to be, until he started taking notice of how much his SS hot was actually healing for. He began revising how he played his paladin and finally settled on getting more mp5/haste/sp over pure intel. Now i can tell you, he is a superb healer, he gets some fantastic numbers and almost at the end of almost every fight, he points out his mana pool to me, most times being above 90%. Now he admits he is a bit overstacked on mp5 and could use some more SP, but the idea is simple. With enough mp5, you're able to cast Flash of light almost consecutively without losing any mana, as your gaining more than it actually costs.
Ok, i'm not telling you how to play, and i'm not saying intel stacking is wrong or bad, i'm simply suggesting a new way of playing. Who knows, you may get a bit more out of your gear than you've been getting lately. This may or may not be relevant to doing 25 mans as i haven't done 25's since t7, but just something to think about.
Oh, and i do realise i said this was gonna be a 'quick post'. Lol. Btw, he doesn't generally go over 20% OH... pretty crazy for a holy paladin, dont you think?