Your [citation please] got me looking. https://latin.stackexchange.com/questions/7159/etymology-of-... ; Google Scholar seemed to provide some references in a search for 'salt salary etymology'.

It is somewhat documented, well documented perhaps.

Correctly documented?

I never finished the recent popular book 'Salt'. After a few chapters it became tedious, repetitive, plus the book consistently omitted tying text to sources. A frustrating read.

As I didn't in fact tie Salt to Roman soldiers' salaries, that was your reading, simply salt -> salary, I'm curious what references you could provide for different etymology? I'm genuinely interested, I rarely reply to replies.