We've recently created a new guild (10-man raiding), and we have had some good ol' trouble with the fella.
What's happening is, is that the DPS who get targeted by his DoT tend to die way too often than I would have imagined. And the way we do it -Dispelling it on a target thats high hp, and dont bother dispelling and just outhealing it if the person with it is low- seems a bit odd to me.
Either way there is no reason to ever heal through it, get the person to high HP then dispel them. Make sure you're 3 healing the fight and try doing a few less ball bounces.