Except if the threat is between them and the burrow. Then they keep running back into the threat, only to run away again, over and over until either they or the threat dies.
It would be nice to not have to sacrifice him, and allow the intruders to run into my traps/military instead. I suppose one could create a second burrow way off in a corner of the map, and assign only that one dwarf to it to get him to get the hell away from the threat... I didn't think of that at the time. I've just started playing again with 0.31.05 (I stopped some time pre-40d), and I haven't gotten used to the burrow stuff yet. I'll try it next time.
And so unfolds the dramatic story of my first ambush on a new fort, and my trial-by-fire learning of the new military/burrow/alert system.
I had a couple of dwarves outside. Not only was my main refuse pile outside (now fixed), I also had several small farm plots of the above ground plants going just outside my entrance. I hadn't realized you could no longer grow Plump Helmets on underground soil (need muddied rock), so I had to set up an emergency food source.
So anyway, several dwarves carting the remains of recently slaughtered donkeys out to the garbage pile spot a troup of Goblin Marksmen coming to deliver some Fun to the fort. In the contemplative time offered me by the automatic pause, I set about creating a burrow that was deep inside my fort. I assigned everyone to it, and triggered the alert. Urist McGarbagehauler and Urist McBerrypicker drop their loads and immediately stump back past my line of traps and war dogs to the safety of the fort.
The goblins, being the dutiful Fun couriers they are, follow the fleeing Urists firing off the occasional arrow and charge straight into my meager defenses. A little under half the ambush got caged or crushed and the remaining seven went to town on my war dogs. While the goblins were distracted with a little canine combat, Urist McDeadmeat the fisher dwarf returns from his peaceful, relaxing adventure in the surrounding forests to find his route home blocked by goblins. Not wanting to hog any of the Fun from the war dogs in the entrance, he continued to dance at the edge of sight, taunting the poor goblins about their mothers. Fast forward a few days, and all of the dogs are dead.
The goblins finally take notice of McDeadmeat and decide to see if he'll sign for the Fun they're delivering. McDeadmeat flees, and after a little bit of running around he almost makes it back home. However, the goblins cut him off at the entrance and manage to immobilize him with a couple of arrows. Then they proceeded to unload their entire stores of ammo into him, turning him into a dwarven pincushion. But McDeadmeat is made of sturdy stuff, and still lives! Now that they're out of arrows, they all walk up and politely ask him to sign for the delivery. Urist, always the considerate dwarf, says he's had enough fun for one day and refuses to sign. So, the goblins give him a gang-land beatdown, spraying teeth and blood everywhere. The beating continues for seriously something close to half a season before McDeadmeat finally succumbs to hunger. Hunger!
The remaining goblins then signed the delivery papers themselves, left the package at the door, and promptly left the area.
Suffice it to say, I suspect that maybe damage values and stuff could use some tweaking