Y'know, I've skimmed through the article once again (not read it, just skimmed) and one thing it utterly failes to mention is the in-game mechanics. Which is kinda logical in a perverted sence of thinking because RPGs never have good economies so why bother, but, if you want to push pseudo-logical constructs like "padded armor is light so you hit faster, plate is heavy so you're slow" (which is kinda bullshit - you get tired faster, but you don't behave like a cripple in either chain or plate), you also need to look in the reasons for those kinds of armors being actually existing.
Even if we throw apart the different historical periods factors (which are ususally ignored in the RPGs), the point is, Padded Armor wasn't use because it allowed you to have +8 modifier to the dexterity. It also wasn't used because you could've swung faster in it. It was used because you were poor as fuck and, well, having it is better than fighting General Butt-Naked style. Correspondingly, Plate Armor wasn't the magical impregnable fortress that people paint it to be. It offered better protection, sure, but it wasn't that much better than the chainmail and so in terms of cost efficiency. Let's not forget it was worth a fortune and you could've armed, like, a dozen of men for that cost (who would totally overpower 1 plate armoured knight). Well, I'm kinda pulling the precise number out of ass here, but you get the drift. But it was used more due to the fact that resurrection scrolls were not easily available and life was somewhat precious, not to mention that knights were also supposed to be less mega tanks and more, like, officers (at least in non-retarded armies), so you've paid extra for your precious health and preservation of the chain of command.
And regional differences also played a huge role. The scarcity of iron ore and so forth. Or even the fucking ideology - the Crusades were the conflict of a straight swords vs curved swords and, despite the fact that the curved ones are much more effective for the cavalry, that was zealously disputed by the european broadsword admirers. Damn, I believe in some times and places you could've been easily killed just for wearing the wrong kind of armor or bearing the improper weapon. And we also forget the creation/maintainance tax at some weapons & armor. And just the fact that weapons were breaking constantly and you often needed not new ones because they were stronger, but simply because you've destroyed all you had already (and repairing them wasn't the simple issue of just pounding them with a hammer).
And that's the kind of shit you need to implement in your rpgs, not the balancing crap. Sure, pure realism is stupid in a fantasy game, but let's say you're about to fact a bunch of armor-devouring acid-spitters - certainly wearing some kind of disposable shit armor against them would be better than wasting a precious suit of plate mail (which may be worth more than the treasure they guard). But then, can you actually survive that in the shit armor? That was already implemented in the Darklands, btw, to a certain extent (dragon fights).