OK, 3 points of note...
1. It didn't look that *&*(^£() cold
2. They were at 360 ft and idly asking how deep they should go - to which the answer was "I don't know"
3. The guy with the video camera must be the world's most annoying buddy! If I had been in "Brian's" shoes i would have speared him and left him down there at 400 ft to F&^*((&^ freeze to death!