Scenario of Stone Vigil hm some days ago:

1) people say hi to each other
2) healer start to cast protect, tank runs away
3) everybody start chasing tank who have pulled 2 groups of mobs already and tank them in farther corner for healer to reach
4) healer can't reach tank fast enough and party wipe
5) tank ragequit

I have no other description for tank other than - retard.
Half of "speed runners" are just plain stupid and unable to perform speed run as a default.