Warping out as soon as you start taking damage is something I've only seen in large fleet fights, speaking personally, so I still consider it purely a large fleet tactic. Not to say it doesn't have its place in small gangs, but in Bacchanalian's example it's something that the FC set up ahead of time. Which, I think, is really what it's all about: Do what your FC says. If they want you to bug out when you start taking damage, do that. If they want you to stay, do that. A good FC will be sure everyone in the gang knows what's expected of them.