Cleon
Legend
I think the org MV 6" is due to wearing scale mail in 1E led you to having MV 6" (DMG1, p. 27). Probably doesn't count in 5E so MV as human seems the way to go.
Yes, I would assume that's the rationalization.
Scale is Medium Armour in the 5E Armor rules not bulky like in AD&D, which'd be Heavy Armour in Fifth Edition. Although even Heavy Armor only slows a wearer who doesn't meet its Strength requirement in 5E, assuming it has one (ring mail is Heavy but doesn't have a Strength Requirement).