i once ran Foundry SM with my Marauder and had a healer who would only heal the tank, period. now the tank was as i recall fairly decent, but no tank can have an easy time keeping all of the adds focused on him, and me im more than willing to pull Adds off of the healer, my main is a Sin tank and my in your face fighting attitude is great for pulling adds off the healer. i tell the guy repeatedly in chat to heal us DPS, he is doing a great job with the tank and luckily the Tank is good enough that we DPS don't die except when it came to HK-47. the DPS have to keep the adds off of the healer to prevent the healer dieing, or being too busy healing himself. the problem is however that without any heals me and the other DPS cant keep soaking add damage so we get killed by the adds, without us agroing the Adds it causes a wipe. after that i voted to kick the guy, me and the other DPS were pretty pissed and the tank as well knew it was bad for us, rest of it was a breeze with a new healer who knew better.
maybe a word from tank was all it needed? like "heal the other dps as well as they will eventually get atleast aoe damage and cant keep all off you all time and some may slip past my aggro?" something like that. i dont care at all and i heal all usually. only if it comes to such end that dps start pulling ahead and its hard for me to keep all alive. only then i start complaining to dps. but healing dps/tank or me or anyone for that matter in group is what we signed up for. i dont mind dying and i usually wont heal myself until i am around 30-50% health. unless i am pretty sure there is a 50%+ health loss move is about to come from boss
should have just explained him i think, as it will be bad habit to jjust heal tank. and ofcourse he was doing a good job. healing only 1 and/or himself wont need much skill
but tank should have spoken imo. we wont continue until you heal others something to make him understand lol