Do you really expect that this can be taught in the typical 3 to 4 session blitzkrieg class So much easier to say," be back on the boat with 500 psi in the tank". Which is kind of like saying, make sure you land the plane with a quarter tank of fuelmempilot:What happened to divers knowing how much gas they use and how much bottom time to expect so they could do a pre-dive brief with their buddy? Bad form.