Were Late Roman Ridge Helmets Really lined in Leather?

[Doc]

To answer the prior comment of lining in Gallic style helmets. I believe that a helmet was found with some type of felt or woolen cloth inside the bowl. It is assumed that it is helmet padding. However, there was a liner for a greave and it was leather on one side and then cloth on the other (AFAIK). It may not be a helmet however the idea is the same. It would appear that lining the helmet in oiled leather would protect the metal from sweat. However, having a felted liner over this leather would help further protect the wearer from blunt force impacts.