The holy paladin is not a 2 button healing class anymore.
If you try to heal with fol and hl only, chances are you will suck.
I respecced holy yesterday. I used to play holy in the past but since 3.0 I had respecced to prot. As a tank I've done many heroics and done all but a couple of achievements. I've been healed by all healing classes with great success but holy palas. Everytime I went with a holy pala healer, it was a mess. Even though gear was great, we wiped a lot.
So I tried to give it a go myself and check things up.
I healed all of the heroics yesterday as a holy spec (51/0/20) and all I can say is that it is amazing.
I fell in love with Sacred Shield. This is our most amazing heal. This in combination with beacon and shocks allows to group heal effectively and efficiently.
Mana is a no issue. Divine plea ticking for 1k mana. Its lovely. Never dropped below 60% mana. Never had to drink.
I healed in mostly blues (only epics being t7 chest, some bracers from nax10, badges shield, rep head from argent crusade, and badges libram). Gear optimized mostly for Intellect and spellhaste. I healed warrior tanks, druid tanks, and dk tanks. Some overgeared, some undergeared (even with greens). Did cool in all cases.
At the end of the day all I can say is that holy healing is imba for dungeons/heroics. Most holy paladins out there plain and simple suck and dont know how to use their spells.
Holy shock and Sacred Shield are godly. Dont waste them. Always keep beacon on ur tank. Make some mouseover macros or get clique + some nice unitframes.
cheers and l2p.