Of course. The acetylene will be more bouyant or something. This story could have been me and some of my friends back in the day, except during the day. 17 years old ready to take on a swollen river with only 2 paddles a cheap infatable raft 3 idiots and a VERY nervous girlfriend. After much protest she finally agreed to go...she JUMPS into the raft and goes straight through the deck, if you can call 3ml plastic a deck...disapears. Reappears downstream, screaming her head off, poor lass didn't take it well, even after I sprinted downstream dived into water I didn't know how deep it was and pulled her back to shore. That ended the trip.
Reminds me of the time I had to rescue somebody thinking about leaping off Sitting Bull Falls.