I main healer but when I run DPS in Expert Roulette I tend not to give comms to lazy healers. Sure letting the tank drop really low while you DPS and then using Benediction to top them up works, but it's just sloppy. My comms go to healers that go above and beyond - DPS, buffs, keep everyone at comfortable HP levels so they don't have to constantly wonder if you're actually going to heal them. Basic DPS healers who perform the absolute minimum of their role get no comms. Shaving 30 seconds or whatever off a run sure feels great up until we wipe because the healer was sloppy.