That is really interesting OM, and it makes perfect sense too.

There are probably some organic substances, like baking soda for example, that could hold a lot of moisture and still feel pretty dry to the touch. So the point you bring up about this still adding weight is spot on.

I made some flavored liqueurs a few years back using Everyclear as a base. I made Lemoncello and "Lime-oncello" and I even made a Rosolio. I took some of that with me a few times backpacking. The first two were really good, but the Rosolio was barely ok, nothing like they make in Italy and thereabouts.

I've only got to taste real Rosolio once, and it was amazing. I've never found anyplace that sells it here, and I've looked a lot.