lol. I have noticed that DPS will go full out, procs, etc, even if the tank hasn't even touched a boss. They see a tank running in and it's go time for them. Even so, some tanks get the boss back really quickly, but generally a few people will have been 1-hit in the process.

You'd think by level 50 the DPS will have calmed down and learned to wait a second, but I see this happen more often in lv 50 dungeons.