In my view there are no absolutes when describing a working set. There can be a point when a rest/pause between reps can morph into a complete set it's self. The rest/pause can be anywhere from 10 to 15 seconds in it's original BB'ing concept. Quite a few of the old school type BB'ing programs (high volume) have rest periods between set's of 30 to 45 seconds. Some extreme sets were 10-15 seconds between sets. Is that a set or a rest/pause? I don't know. Sets anyway are just breaks in an exercise before reaching a certain amount of reps for a targeted muscle group. If one is doing a 100 reps as a goal than the sets (breaks) can be 10X10's, 5X20, etc. Or if a goal of 30 reps is the case, than 6X5, 3X10, etc. As far as I know, there as not set rule as to what is proper rest set between exercises is. It's all subjective to the person doing the workout it's self.
When I was doing heavy breathing squats of 20 rep, it might have taken me 2 to 3 minutes to finish one set. Three breaths between reps at the start of the set and maybe 6-8 breaths between reps near the finish of the set. Would that have been one set of 20 reps, 20 sets of one rep or one set of rest/pause reps until I reached the goal of 20 reps? Again, there are no absolutes when reps making up a set are concerned. It depends on the of the person doing the workout and their view and goals. Good Luck.
