I completely agree with your basic point and would like to add that they get frequent diving medicals, are paid to stay in shape with PT on duty, and are very well trained and supervised.
For clarification, a dive this shallow does not require a diving officer or chamber on deck. Naturally there is a whole chapter in the US Navy Diving Manual Revision 7a to help figure it out: Chapter 6, Operational Planning and Risk Management, starting on Acrobat page 301
However, IMO some of the things they do require are very similar to what every recreational diver should do (red emphasis is mine):
6-5.1.3
Emergency Assistance.
It is critical to coordinate emergency assistance before
an operation begins. Three types of assistance may be required in any diving
operation:
- Additional equipment, personnel, supplies, or services.
- Clarification, authorization, or decisions from higher command.
- Emergency assistance in the event of a diving related illness or a physical illness/injury.
The location of the nearest recompression chamber shall be identified and the
chamber operators notified before the operation begins. The location of the nearest
Undersea Medical Officer and medical facility shall be located and notified. If
the duty chamber maintains an on-call or on-duty UMO watch bill, then there is
no need to separately contact the UMO prior to the dive.
Sources of emergency
transportation, military or civilian, shall be established and verified.