Im currently seeking investors for my new and improved underwater cattle prod (compliant with EU 1099/2009, CE, and NORSOK). So far I've done 3 drawings on a blackboard and as soon as I can transfer to pdf, I'll contact all interested parties.
In the interim I find the combination of those annoying scuba rattles, some KY and a love for dark restricted places helpful
A shit diver is a shit diver, theres a lot of them around. If they're still doing that at instructor level, it probably says more about the system than anything else.