Leather Cuirass

[Dan Howard]

The fact that helmets could be easily punctured by spear-butts (with kinetic energy of around 60J) or nails, but could resist hand-blows/arrows with 30-40 J kinetic energy shows the armourers were walking a fine tightrope between lightness and resistance.

If you place a helmet on a rigid surface and give me a hammer then I could easily drive a pencil through it. Try doing the same thing while it is still on someone's head. My point is that there would be no inconsistency if the helmet was both proof against battlefield weapons while still being susceptible to a nail (yes I think they are nail holes, not butt-spike holes)

IMO thereis no way in hell that Trajan's column can be used to support the theory that segmentatas were made of leather. It can't even be used to help someone make a replica of a metal one.