I suspect the bending of the rules that went on to facilitate the flight require scrutiny, but at the end of the day it was still down to the PIC to make the go no go decision. It is called freedom of choice.
I couldn't agree more.
The way I see it is that the CFI (or 'de facto' CFI) shouldn't have asked for the flight to go ahead in those conditions. BUT, at the end of the day he only asked, as bose-x said it us freedom of choice, the old saying springs to mind, 'Would you jump into the fire if I asked you too?'
I cannot understand why delving into the working practice's of this 'certain individual' regardless of their nature, which has be insinuated on here, bares any relevance as to why this accident happened.
Maybe I blind or naive, but to me, from reading the report, the chain of events that occurred that day make it obvious why it happened and I think that an awful lot of Students and existing Private Pilots can learn from what happened.