A good raid can be the most rewarding and exciting part of your World Of Warcraft experience. When teamwork and skill combine in a good raid party, objectives are easily met and your entire group hearths home without resurrecting.
But when your raid group is formed on the spot by someone with less than existent leadership skills, you are in for a world of hurt. These groups are often the type formed when an area is hit by an organized opposition's raid. At this time, the need for a raid group becomes apparent, and somebody steps up and starts the group. But a defensive raid group should never change to an offensive raid group without first setting some kind of objective.
These groups get gung -ho when they route the enemy, and the group quickly becomes a train of "HK seekers". Snaking into enemy territory chasing after the tail end of the retreating enemy, soon they meet the organized resistance that's been formed at the nearest enemy town. The newly formed battle line is fiercely contested for a few minutes, but the defending enemy has the advantage of respawning guards, and every raid group formed since the conception of WoW has had that 1 (or more) guy who stirs up the guards.
At this point it's best to call a general retreat. Since that never happens with these "pick up" groups (they always think they can turn the tide back in their favor), your smartest act is to hearth out and leave with dignity.
So lets say you are one of the folks that should have left already, and now face an overwhelming number of red names. You are gonna die, accept that and prepare for it. We are gonna leave everyone else now. If you are a support class, don't feel bad, you can't help much now anyways.
Don't run down the path you came in on, everyone else is doing that, and it only serves as a focusing point for the now "HK hungry" opposition. Find a route that nobody else on your team is taking and head that way. You don't even need to be heading in the general direction of your intended retreat. Remember that we are hearthing out, so it doesn't matter if you do this 100m further away.
If you have no pursuing fan club, then hearth out and count yourself lucky. If you do have your own train, "root em if you got em". If you can't root, at least draw them as far from your main group as possible. This way you still serve a value to the rest of the team.
If you are going to get nailed, try to find some trees or hills that you can res behind after you go down. Ashenvale and Tanaris are great for this. This will give you a chance of escape if they corpse camp you. Res behind a visual obstruction, and once they see your corpse change to bones, they will run all over looking for you, but you have a head start because of the cover you took. Now just find a safe place to hearth, and end this nightmare.