[quote=SyrianHamster]Does this make sense to anyone?[/quote]
Makes sense enough to me.

[quote=Meeky]
This is reflective of feudal times. You didn't see armies of men wearing full plate and carrying nice metal swords and shields. For one, that's heavy. Also, it's really expensive to field an army so well-equipped.[/quote]
If I'm not being uncouth by butting into this line, that's not entirely true in case of our period to my knowledge, or at least were it not for the unusual circumstance of complete subcontinental balkanization causing two decades of chaos. It is around this time of serpentine gunpowder that we'd start seeing munitions-class armor start getting churned out by guild workshop. And for that matter, neither is a sword especially heavy, with the heavier end of the zweihander class reaching seven pounds at most; the issue of fatigue comes from extended combat action in less heavy and more suffocating armor, not that it wasn't heavy, but the primary source was lacking ventilation compounding extended actions. Chain-draped heavy quilt gets VERY hot, and chain is often rather heavier than homogenized plate.

[quote=Meeky]Instead, you'd have a pool of professional soldiers, such as, yes, a house guard, that really did make a living out of warfare. Knights and huscarls are prime examples of such men. However, large professional armies didn't really become a "thing" until much later; a local lord would just gather up a bunch of peasants from his fields, equip them with weapons, and march them off to war. (Consequently, you usually saw a lot of people running away and deserting their armies in battle. This sort of behavior continued well into the 1700's.[/quote] 
It is to my understanding that this is not entirely true either. Besides gentle-blooded or knighted house guards, there were also mercenaries in the employ of lords as said guard. This in addition to further mercenaries bought for a campaign, and in addition to whatever the crown would commission. This in addition to institutions of martial familiarity like those for the English longbow meant that the core of an army was to consist of professional troops, and the core would be quite a large portion, of mercenaries and men-at-arms (knightly or otherwise.) If a belligerent was using peasant conscripts from the field, in the field, it was likely a sign they were losing already to draw so recklessly from the harvest. Large professional armies they were not, but neither were they small, with support in the form of some number semiprofessional troops drawn from the commoner.

[quote=Meeky](The Revolutionary War in the U.S.A. is riddled with examples of militia running away as soon as the enemy closes in on them.)Making sure your armies are well fed and such is important. [/quote]
Wouldn't this be more that the militias were typically guerrilla fighters in the first place? My understanding is very basic, but they were not meant nor expected to hold a line against the British without a dugout, they were to harry the enemy long enough for responsive action, hold fortification, or else were bushwhackers killing in the woods and dying in the woods. Dying less than British line infantry, though.

[quote=Meeky]Most casualties in war have historically been from disease and injuries not being treated properly, so keep that in mind. A healthy, well-fed soldier is less likely to succumb to disease than a malnourished one.[/quote]
Quite right there. Carry on!