Don't be afraid to let it drop down to 50% in dungeons. Few hard hits there that are problematic. In FF you have the ability to bring up a players HP rather quickly, opposed to WoW where you have to spam weak ass placebo heals while waiting for your large CD heals to come off cooldown.
I generally only start casting healing once the tank drops below 50%. Rest is DPS.
In savage, you usually do not get that option, these encounters are designed for both healers to bring up the raid ASAP.
Personally, I find 4mans a snoozefest to heal, no matter what class. Yeah sure, flopping a card every 30 seconds is nice but you'll quickly learn that not all of them are terribly useful and burn most of them to get the added effects for the next one.