The rubber gloves stay dielectric even if the liners are wet. Ideally, the user would change out the liners once saturated tho. It is amazing how some guys sweat soooo much while others do not, not at all.
I have seen linemen that came in with FR shirts, and a couple hours later have to change them out because they are soaked. I have even seen guys put the wet shirt on the truck side mirrors and drive around like that to dry them, then put them back on in the afternoon because the 2nd shirt was saturated...crazy!
The company I worked for had an incident whereby a lineman was burned because the current was conducted by the salt in his sweat. His stomach was badly burned. High voltage does crazy things for sure.