Linothorax vs Quilted linen vs spolas

[PMBardunias]

For instance, kune, perikephalaia, and kranos are all used to refer to helmets within the same or similar lists; since it is evident with other categories of items that they tend to use one term to refer to one kind of item, it seems likely that these were used technically to refer to different classes of helmets.

I agree this is quite important. I have just started combing through the original Greek, and "thorakes" is used in many ways. Sometimes simply as "thorax", implying that the word itself was sufficient to tell the reader that a, presumably bronze, cuirasse was meant. Other times the phrase is longer, as in "for the thorax", using throax as an anatomical reference and not a item of panoply. Getting all the references together and looking for changes in use both temporally and geographically could be very interesting. Determining why a given author used which term is needed.

Also against this idea is the fact that we hear of 'thorakes lineoi' but not 'spolades lineoi' in Xenophon etc ( and he, if anyone, should know his Greek military terminology! )

If spolades meant simply a hanging garment like a blacksmith's apron, then became the slang term for a T-Y based on construction, Xenophon might not care if it was made of linen or leather. Such things are important to poets, but perhaps less so to a man who is interested more in function than form.

- unless you want to postulate that linen armour was not Tube-and-Yoke at all, but what you call 'vest-cut', like a bronze muscled cuirass.

Not all linen armor, but perhaps some and some leather as well. Especially early, there are vest-like non TY armors and they need a name. That is not to say each instance of the word Thorakes coupled with Lineoi implies this, the term thorakes is obviously used both very broadly while also very narrowly to indicate Bronze armor. It is not so clean though, because a Spolades could be a TY, but it was also armor for the Thorax, thus both terms could be applied. This discussion has always centered on material, but I think it may need to shift to form.