Well sky diving is very different IMO. Not a expert, but did a few jumps when I was younger. If your students need such a talk, they are all in tandem anyway. They going along for ride only. There nothing they can do to get away from the instructor, I am not even sure if there anything they can do to hurt themselves. The instructor has full control of the suit. By the time they can jump by themselves, they would have jumped enough tandem, know the risk, fold their own suit ...
DSD in 40FT of OW analogy to sky diving is like going to 10,000ft, the instructor prepare the suits, put them on the students, tell them pull as soon as clear of the air plane, then maybe give the talk like the one you described. Then they jump on their own. After 3 students jump off, one instructor follow and hope everyone land safely