Question about quad shamans + pally and "Self Preservation Mode" in 5v5

For 5v5, 2 players, 1 Healadin and 4 Eleshamans, when if ever would it be the optimal strategy for the shamans to stop DPSing and go into what I would call "self preservation heal spammin', totem droppin'" mode?

I play the holy pally so when I get CC'd, I'm acutely aware of my sudden inability to throw some large heals on one of the shamans. I have to make a judgment call at that point whether to bubble or use the trinket. Using the trinket, I don't mind so much, if I need to, but if there's a priest nearby, and I'm CC'd (but not cycloned), then using the bubble would probably be a waste of time.

So that brings me to the question -- when should I ask my shaman partner to switch modes until I recover from my CC, or should we accept the *potential* loss of one of the shamans as an acceptable risk in return for continued focused fire?

I asked my Paladin healer, he said you should Hammer of Justice the Priest in that scenario and Bubble.

Ellay, thanks for asking your healer. I'll try to do that next time.

However, the broader question I was trying to ask, I guess I didn't word it right.

When do you decide to start spamming your heals instead of waiting on your healer to get out of whatever trouble he maybe in (cyclone/stun/sheep/counterspell, COT, whatever..)?

I can only guess that if you see one of your guys drop below some percentage, you might start to panic and decide to throw a chain heal.

I'm just beginning arenas with 4 shaman + pally setup and I go into heal mode right after I kill a dps if need be. You should be able to take out one of their dps before they can take out one of yours at this point healing up to full should just about put the win out of their reach.