A friend of mine, [@Eisenhorn]has given his insight in the matter. The following was what he said;

[quote]"Frankly? Assuming the enemy is without numbers here, which I assume is the case?, and attrition is the goal, booby trap and create a sheer meatgrinder for any who enter, and hold the narrowest point of the pass. 

Pungi sticks, rockslides, pitfalls, free fire zones for archers utilizing flaming arrows, cause as much death and discord amongst the enemy ranks. 

Only reason to make a braekthrough attempt would be to kill the enemy commander if he was foolish enough to be within reach and then that can be considered schmuck bait, since one would assume a last effort would be made to cripple the enemy.

Oh, and seal the pass behind you if at all possible. Men fight hardest when they've no chance of survival, there is no reason to hold back in the hopes of seeing another day and it'll slow the enemy progression after the 1200 men are finally slain."[/quote]

Nothing much that hasn't been said before, although it seems that it is the most voted course of action.