Could/should I do rescue?

[dmaziuk]

... the victim was beyond resuscitation by the time they had the defibrillator attached. Circumstances could not have been more in the victim's favor: a Rescue class, all geared up, having prepared to do an underwater search ...

That illustrates @tbone1004's point rther nicely, unfortunately: middle third of the rescue class is most likely body recovery anyway.

We've an SSI LDS here, they run "React Right" CPR class (incl. oxygen and auto-defib, apparently) and "Stress something" for the recognition and prevention component. So if one wants to learn specifically rescue, those two would be a better option. If the goal is to become a "better diver", I'd look into some sort of intro to tech myself...

 

[Lorenzoid]

The retired EMT said that he had done around 200 resuscitation attempts in his career, none of which resulted in a "save."

 

[woodcarver]

Unfortunately, without an AED, CPR and breaths are only an attempt to buy the victim time. I agree with tbone in that rescue breaths in the water are not advised. Get the victim to the shore/boat as fast as possible. But I don't agree that Rescue is a waste of time OR money.
Diver0001 and Jim Lapenta have already espoused the value of Rescue quite well. Take the class. I've always advocated that it is up to the student to extract everything an instructor can give them. A good instructor will give up that knowledge happily. If you have a question, odds are, someone else in the class does to-ask it.
This cert is NOT one I question if it was worth the time or money.