Great story. That small CFI sounds like someone straight out of a Gann novel...

Slats, slats... ? Oh, had to look again; leading-edge slats.No idea. I unfortunately didn't talk much with Bill; as usual there was a small crowd of noobies around who had zillions of less arcane questions, and as drawing the ignorant masses back for another show is so vital to this museum, I let him do his thing for their benefit. I'll remember for next time: Slats- fixed or not?
I guess the taboo about the doors is related to them maybe banging around unecessarily... reminds me of the fact that I was admonished more than once during my training for forgetting to dog a Cessna window before takeoff, yet it's perfectly safe to fly with it open at most speeds. But fussing with an open window is the last thing you want to even think about when climbing out; I never understood why any CFI would even mention it until we'd levelled off. It was always: "Window...!! No, not now; what are you doing?!" ::)
I did once have an instructor who enjoyed opening the door(!) of the C150 in flight and leaning out to place his foot on the gear-leg footstep (with seat belt still on, of course!). He insisted, in fact, that I try it too- I'm glad he did

. It was fun. No big deal with the resulting minor turbulence inside; just had to make sure the chart was clamped down first. And I found I could easily maintain heading and altitude when he had the right door open. You might say it was educational, in that sense. He was, shall we say, not so uptight. But a very good pilot and effective instructor; all business when it counted. Taught me a lot about how to scan the instruments while primarily looking outside...