The thing that drew me into the thread was the very scary ability to identify (from my perception of Andrew Walkers position) with the possible chain of events that lead to this tragedy.
HappyFran,
I think a lot of us felt that way. I know I did.
It's all very well to say that someone has a PPL and they're PIC and that's the end of it...but human nature doesn't work that way. You don't go overnight, just because you've passed a Skills Test, from doing exactly what your instructor tells you, to completely ignoring all his/her advice. You don't say "I'm PIC, therefore I will ignore the advice and opinions of pilots with zillions of hours more than me, because it's my decision". You especially don't do this if the instructor/more experienced pilot is a lot older than you. You listen to advice. Most people even suggest that this is a good idea, if you're a low hours pilot. Not listening to anyone is generally perceived as arrogance and over-confidence. Where do you draw the line?
So, leaving the law and who was officially PIC out of it, this is a very scary scenario that many of us can identify with.