Your set of armor is what most players use in combat. Some speak of using multiple mail shirts, but otherwise, you cannot make your set of armor heavier. The armor will slow down each dwarf at different rates, based on each dwarf's Armor_user, Strength, Endurance, and maybe other attributes and skills. Because heavier armor exhausts a dwarf quicker, causing less sparring and more resting, some players train dwarfs in lighter armor.
The real problem is dwarves getting tired right? So if I'm not seeing dwarves die to exhaustion (and subsequent beheading) does that mean I can be confident that weight isn't a problem?
Yes, but if you see dwarfs becoming exhausted and being beheaded, it might be because they are exhausted for other reasons.
You can see other sources of exhaustion. Two examples...
- tired creatures stop to rest --- give one axe dwarf an order to kill some wild animal - you will see both the axe dwarf and the animal run some, then stop to rest, then run again.
- physical hits also exhaust the target --- you will see a wild animal being punched by a group of dwarfs, the animal passes out, wakes up, is punched several times, and passes out again without having moved or attacked the dwarfs.
I mention those effects because, while it is obvious that a military dwarf can become tired from attacking and from carrying the weight of armor, it is less obvious that charging, dodging, and being clubbed by weapons, also will tire a dwarf.
(I have the opinion that armor deflections can reduce the exhausting effect of being hit, but no way to verify it)So, if you combine this idea of exhaustion being caused by every action of a dwarf and every action by their opponent, with the idea that dwarfs often face larger number of opponents, and the the idea that a squad has a tendency to become split up during combat, you will still see dwarfs killed because they became separated from the others and were clubbed into exhaustion.
From the combination of these observations and ideas, I would say this... the best way to avoid death-by-exhaustion in situations where the enemy has the numbers, is to choose to fight in corridors (10 to 20 tiles wide seems best) so that as your dwarfs charge forward, the tired and injured dwarfs will fall behind and the untired dwarfs will push forward.
I know others have put this message out there, but I wanted to preface the message with all the contributing observations and ideas.