The argument for healer dps has nothing to do with how much damage the dps and/or tanks are doing. Once you reach the so called "healing cap," any additional healing is a wast of time and mp. At that point, your options are to do nothing or to dps. And just to give everyone an idea of how little healing is actually required, you can go to fflogs and look at the fastest clears for Creator Savage before echo, and the fastest one for each had both healers in cleric stance for at least 70% of the instance. Obviously the groups are pretty hardcore and are masters of their classes, but it just doesn't add up at all when other people say they have zero time to dps.