I have experienced what I can only describe as griefing by certain pivotal roles on lesser-run dungeons. Here's an example:

I had a group of three - a healer and two dps - which queued for The Thousand Maws of TotoRak (level 24). The role we were missing (tank) was the one that was in high demand, which is often the case. Unfortunately, that dungeon is rarely run, so we had what I can only assume was only one tank queuing for the dungeon. This person would let the 'Duty Ready' countdown go all the way to a few seconds and withdraw. That person then queued, waited, and withdrew again, again, and again. After realizing there was no other tank and experiencing this nearly fifty times, we finally withdrew and had to re-queue.

Has anyone else seen/experienced anything similar? Is anyone reading this *doing* what I am describing? If so, why? Could SE implement a queue-per-hour limit of, say, 3-5 times?