I wonder how this happened.

[Vtach]

OR....ask the United States Coast Guard on their advice on the best way to dive from an unattended boat.  ;D

I would bet that there are quite a few experienced Great Lakes divers out there that would not recommend this practice. 

People often want advice on how to do something they are set out to do regardless of whether or not it is recommended, safe or legal.  So they generally ignore everything until someone tells them what they want to hear.