Just gauge the healer when you join into content. Pull what you think is appropriate for your skills and their gear. If they keep up and there is slack, pull more. If you die bc you thought they could handle more, take it on the chin and apologize for pulling too much (even if its their fault). If a healer asks you to pull less, pull less - if they ask to pull more, pull more. Curse them under your breath for being bad/lazy/whatever but keep it out of the chat. If they are THAT awful vote kick and move on with the day.