MScorpa
Registered
I'm guessing you have never been cave diving before...
In ALOT of caves there are only occasional places to turn around. There is no way to remotely (like a body length and a bit away) hear "excessive bubbles". Normal bubbles on the roof can make a ton of noise while an actual failure like a leaking 2nd stage can only make a modest amount of noise.
I have no interest in caves but have been in my fair share of tight spots. Yes it is certainly true that bubbles may not be heard or felt, but my point was; if the cave is that tight you're never going to be able to get your hands on the donor's 22" hose anyhow so the benefit of the z-system is what again?