As I understand the facts, Dave was not a "professional pilot", ie. he did not earn a living by flying. Although he was involved in High Performance Aircraft Training, he was not a flight instructor and did not give flight training.

Jeff and DJ,

 

That may be true about Dave in the sense of flight training.  It is my understanding that something called "familiarization flight time," the 5 or more time-in-type hours frequently required by insurance companies, can be provided merely by a private pilot "observing/commenting" in the right seat.  I have done this myself recently and endorsed the familiaree's logbook for this activity (including advice given on the ground).  I don't know whether Dave ever did that kind of activity or not.