Bear in mind that (1) our view of the effectiveness of historical armor types is in hindsight, and (2) game stats for armor are based on this long-after-the-fact view. Even in times and places where both the materials and expertise to create armor varieties A and B were in abundance, the fact that we know
now that A is better than B – and put that information in our games – is no guarantee that hundreds of thousands of warriors over centuries of warfare didn't believe that B was a good idea. Maybe B had attractive features that have nothing to do with what
GURPS would sum up as DR, DR/$, or DR/lb.:
- physical convenience at a level too small to rate in the game (a "-0.1 to DX" giving -1.2% to odds of success still means something when 10,000 soldiers experience it)
- coolness in battle or on the march
- warmth (or better compatibility with warm garments) in cold climates
- stealthiness (or just not annoying the living hell out of people or animals with its racket)
- less tendency to catch on and destroy clothing
- less tendency to catch on and pinch flesh (causing sub-HP level injuries that get infected)
- ease of maintenance in the field
- ease of keeping clean (making for a shinier and more impressive show for the bigwigs and/or civilians)
- pure intimidation factor when facing "barbarians" ("Holy hell, Karl, these guys are made of metal!")
. . . you name it.
There's this belief among gamers that somehow, after the first person or first few people or first entire army was lost because of crummy armor B, everybody would stop using B and start using A. But that assumes A was right there to compare to B; that the losses were clearly attributable to B rather than to bad tactics, unsuitable weapons, horrible weather, low morale, or just bad luck; and that word of all this made its way across the pre-electronic, pre-motorized world to every warrior, general, lord, and king with a stake in the matter.
In reality, of course, that didn't happen. Ask anybody who has served in a real war (me, I've spoken with veterans of WWII, Korea, Vietnam, the Gulf War, and a few smaller actions): Soldiers carry
garbage into battle all the time. They are ordered to do so, and the same lousy gear sometimes hangs around for the next war and the one after that, getting people killed but being imposed on troops just the same because somebody far from the dying felt it was a good idea based on some tests or because the factory was located in their district or riding, or even because it was tacticool. This is in recent times, with scientific testing, OR, statistical analysis, and high-tech means of disseminating information.
So . . .
Think of armor that loses the DR/$ or DR/lb. contest as being needed for historical settings. Players can use their "meta" knowledge to choose A over B – just as they can see every counter on a battle map and make decisions in combat based on that, use their knowledge that "this is a game" to optimize stats, and exploit their awareness of the genre to know what threats they can safely discount. This is the "hidden edge" of adventurers in adventure games. Look at it as a positive thing: It helps explain why the heroes prevail without resorting to more ham-fisted methods such as dice-roll fudging, or to controversial game mechanics such as "fate points" and Luck.
This extends beyond historical games. In fantasy games, the savage orcs who attack in hordes with a "life is cheap" attitude can clank around in inefficient armor B because they just don't care or because they think it looks badass, while the civilized heroes can optimize their armor and be better protected while carrying less weight and spending less money. No problem.
(And arguably, a game
needs this aspect, because the mini-game of finding the optimal gear, spotting loopholes, and avoiding pitfalls is the Hurting Wrong Fun of a huge number of players. An RPG that denies them the mini-game denies the publisher sales . . .)