The other day I was only queueing for MM Hammer Station as I wanted to get the weekly done quickly. Eventually get a pop and we wipe on the droid boss because the healer doesn't cleanse the stacks. Check his achievements and he has never done a Master Mode fp, that's fine, so I tell him he needs to cleanse the stacks off at 5 stacks to which he responds "I thought I only had to heal". Yikes .... anyway, eventually he learns that expunge is what he needs to use, a wipe later we have him with his cleansable debuffs increased in size, still wipe. Probably wipe 2 more times then he just drops group without saying anything and we clear the boss with a heal comp and eventually another heal joins and we complete the fp.
I queue up again and guess what I get... the great healer has returned but hes now queued as DPS, and he has his friend in 220 DPS gear and DPS spec queued up as tank.