You're not supposed to be energy neutral while eating focus fire - though the self heal and bubble HoT helps. Don't neglect polarity shift and overload either. If you're not taking the instant AOE heal on overload and spamming it you're doing it wrong - it's very good. You're going to keep innervate on cooldown even if people go to interrupt it because you're probably going to get at least 2 ticks and right after that you're going to follow it with resurgence into dark heal. You can use resurgence into innervate if you're not being focused but I think people don't realize that when you are being focused you want to use resurgence on dark heal for burst healing.
This is why sorcs benefit inordinately from having a second healer. They can go invincible and get healed to full, even while stunned, sit in their cuddle puddle with HoTs on them from an operative and consume themselves to regain mana, and when needed pop polarity shift for the anti-interrupt effect - particularly if their resolve bar is maxed.
Overload you have to use sparingly as it may be the difference between stopping a cap and not. I cant tell you how many times voidstar/civil war my overload stopped the cap. In pve overload is a great trick for getting health back while using consume. Basically consume down, shield, self heal, overload and you are back at full health full energy.
But if im being focused, if Im kiting, of course I through overload in (it crits at about 3k), but in terms of healing my team, it gives 1 burst then on cd, which is why generally I save it for 1) when im focused or 2) when someone is capping.
And yeah of all the healers sorc is the one who likely benefits most from a 2nd healer.