Running your BCD / Dry suit off your Pony?

[ClayJar]

Quoting from the linked article:

In the case of CO2, there have been anecdotal reports of rashes developing in humid areas, such as the armpits, due to irritation resulting from formation of carbonic acid by reaction of water and CO2. The additional possibility of interaction of CO2 with the diver's physiology should discourage carbon dioxide use[...]

The carbonic acid irritation had slipped past me, but it makes sense. (The article also mentioned the two-phase state while under storage pressures.)

As for the physics, that was a nice summary, even if they refrained from actually mentioning the term "mean free path".