Considering we're covering how coverage doesn't necessarily interfere with mobility, the relative rairity doesn't matter.
It does because, for one, the IRL character designers don't have much frame of reference for that sort of thing, for another it places the historic development of such things as
very painfully specific in its breakdown, for a third it implies that one
has to have very extensive development of
specifically full plate to work out such things, and finally it is a
rather large amount of material as far as armor is concerned because the methods involve multiple layers of overlapping metal plates
fully covering the range of motion while managing to not obstruct it.
Full coverage means you have to do something for the joints. And doing this without sacrificing flexibility is very,
very complicated, such that it only
barely occurred IRL and was done primarily as a damn
fashion statement because the armor was actually obsolete when made.
Third of your weight? If you're tiny I guess, yeah.
Given the weight is largely in the range of 33-55 pounds, "a third of your weight" is a
bit of an exaggeration needing the higher end of the armor and a rather lean person, but it's hardly ever going to be under a fifth for all but the lightest armor or the heaviest combatants.
And 165 pounds isn't exactly
tiny, it's just
lean. Not realistically seeing that in a career soldier unless they're particularly short, sure, but plenty of simply healthy people are going to be not far from the heavier examples of full plate being a third their weight, and even for outright strongmen it's going to be close to a quarter their weight for the heavier examples. And besides, "a third" was an off-the-cuff basically
guess. It generally being close to a quarter to a fifth isn't exactly far off for my point about inertial factors of mobility.
You know what else adds weight? fucktons of gear and the occasional combination missile jetpack.
Exactly. The
full kit of a Knight would hardly have more than 15 pounds over their armor because it amounts to a polearm or two-handed sword, a one-handed sword as sidearm, and usually a dagger as a finisher for other knocked-over Knights. Meanwhile, Mandalorians have
boatloads more egregious options for weight concerns to mobility, and those jetpacks
will fuck with center of mass.
