I recently got the whirl spell...wow, great spell. But, I was
wondering, what sorts of things make it break? It never seems to
last very long, certainly much shorter than root does.
I'd like to know what actions to tell my group members not to do when
it is in effect, to make it last as long as possible.

Does CF or Choke kill it? What about wizard dd spells, bash, or monk
attacks?

Thanks,

Eryx of Innoruuk