Bob DBF
Contributor
Why? Better to practice better gas management techniques, carry a pony bottle, make sure you can drop your weights if needed.
You practice CSEA for the same reason you would any other skill.
As far as dropping weights, at depth you are going to be doing a CSEA or buoyant ascent, dependant on configuration, whether you were planning on it or not.
As has be said before, the CSEA is the last in a list of emergency procedures for dealing with OOA, before a buoyant ascent. If done properly, it will put you on the surface unharmed if you are within NDL limits. When I started diving it was used regurally by new divers who had no SPG, j-valves that got knocked out of position, or k-valves, untill they learned how long the tank would last. It's not needed now, unless one finds themselves OOA without a handy backup, which is a poor time to learn an emergency procedure.
It has no effect on me, as I was trained and make a practice CESA on a regular basis. It might make a difference to a new diver who has panic to fall back on in an emergency, which I have rarely seen to have good results.
Because one knows an emergency procedure does not mean you have to use it. I have a pony bottle that I have never used in an emergency, should I just stop carrying it altogether?
Bob