My group is trying to get a viable strategy for a 3 heal comp. We've gotten it down with 4 heals but due to some issues we had to move to this. What we are doing so far is 2 healing one group and 1 healing the other. The 1 heal group is having issues keeping everyone topped off and alive throughout the encounter even though more often then not they will make it to 20% alright and then get slaughtered after that. I've seen videos and strategies where a disc priest will stand in the middle of the groups and heal both, or a resto druid runs from group to group. We haven't tried either due to no priest and an undergeared resto druid. As of right now our groups move together to their designated crystal wherre they will take the stomp and the crystal people do their thing then we move to the next one. I've heard that taking the stomp first then having the people move the crystal gives the healer, who is soaking with tank, to top off those individuals before the crystal goes off. Not sure what's the right move, looking for some advice so we can go back to working on other bosses. Our comp is:
G1- Resto druid, Resto shaman, prot pally, hunter, rogue
G2- Holy pally, druid tank, dps warr, mage, lock

If the comp isn't right either please let me know.