Subarmalis or gambeson?

[Flavivs Aetivs]

I think mail was indeed worn without padding. I just think padding started coming along in the 4th century as different shield shape and longer weapons (e.g. Spatha and Contus) meant you were getting hit in the body more. Hence it's heavy use in the medieval era.

I think it's an evolution. Just like Helmets.

Also, looking at Beatson's reconstruction this is how I always thought the Byzantine "Banded" Lamellar was assembled. Except I thought the Edging was also a backing, but the backing wasn't part of the structure of the Lamellar.