SolitonMan
Explorer
Page 284 of the DMG in the description of mithral : "Heavy armors are treated as medium, and medium armors are treated as light, but light armors are still treated as light." Only seems complicated if you're going spend too much time parsing words and thinking about it. I never even considered it an issue until I saw people discussing it on the boards. Always seemed obvious that mithral breastplate is light armor, and mithral full plate is medium armor.