Just to clarify for my own knowledge, isn't ABT from beginning of descent to beginning of ascent? So shouldn't the time at the safety stop be subtracted from the total when using tables?
I was never taught to subtract safety stop time. And don't teach to do that either. And in this case 3 minutes is not going to make much difference. And remember the safety stop is optional so it may actually be skipped, so why subtract it? I teach students to err on the side of conservatism and to plan and track dives as square profiles as my agency requires me to. Even though we know they are not. Standards require me to teach them as such. My PADI classes were all based on square profiles when I got certified. I was not taught to fly the computer. In fact just the opposite. I guess now it's different.
If using the PADI tables exactly as intended, the bottom time begins as soon as you start your descent and ends as soon as you begin your direct ascent to the surface at 60 FPM. The ascent time and safety stop are not considered part of the bottom time.
So let's look at how this applies to what we know or do not know about this situation.
1. We do not know if the given times were total run times or bottom time as defined by the tables. We do not know if the ascent and safety stop were included in those times. We really can't make any real assessment of his dive in terms of tables because we don't know any of the real numbers for sure.
2. We do know that the ascent rates were slower than 30 FPM--apparently considerably so. The bottom times in the PADI tables were computed on the assumption that the diver will ascend at 60 FPM--ascending slower adds to the bottom time. We also know that the diver's ascent on the first dive included a barracuda-watching diversion that should be considered part of the bottom time. Since he did not begin his direct ascent until after that, then the barracuda watching time is part of the bottom time. If the times he gave us were actually run times and not just bottom times, then it doesn't matter.