This often comes up in these types of discussions.
In his history of NAUI, Al Tillman (NAUI instructor #1) talks about the meeting of instructors in Houston in 1960, the major event in the founding of NAUI. Tillman was then the director of the Los Angeles County program, and he had learned his instructional technique at the Scripps Institute, the place that invented formal scuba training. In that Houston session, instructors from across the nation demonstrated instructional techniques with the goal of establishing minimum standards for instruction. Tillman and others from his organization were very surprised to see some of the instructors using harassment, like removing masks and shutting off air, as a part of their instruction. They had never seen that done before. NAUI did not include that in their minimum standards or their procedures, and Tillman and others felt it primarily benefited the instructors' need for amusement.
They did not forbid it though, and to this day NAUI allows instructors to do pretty much whatever they want as long as they meet the established minimum requirements. As time went on, agencies discouraged or disallowed the practice. Even with the agencies that disallow it, though, you will still find individual instructors who will do the same thing.
This brings me to the main point of the post: the fact that certain activities were a part of you instruction in the old days does not mean it was part of everyone's instruction in the old days. Harassment and difficult physical challenges (like doing pushups in full gear) were indeed part of some training programs, but they were not part of all training programs. It all depended (and to some extent still does) on the individual instructor.
