I agree completely 'remoak'
We both acknowledge that training in GA is at best basic at worst down right dangerous & I reckon mainly due cost sadly. I work at the high end of GA & the checking & training is excellent.
Two of the pieces of the Swiss cheese for this guy was one, training & two the actual A/C. meaning that he obviously wasn't too prepared for such an event & the A/C should have been able to sustain flight on 1 engine all things equal. BUT at this stage we don't know how 'equal' this guys mount was on the day.
Funny you know we have had pilots with many hrs on heavy jets/large turbines come work for us for various reasons & all bring vast knowledge but most struggle with SP Ops & the high demand of our work at all hrs so experience in some ways isn't of benefit funnily enough.
I still believe you can train a pilot to be the best in a controlled environment such as a Sim but under real pressure he/she can turn to making even the most basic mistakes, humans not the machines is the real problem
Just as an Eg of well trained pilots some years ago now pre Beech 200's the "RUFDUS' used C404's. One night a flight could have turned to poo big time with the loss of an engine in IMC leaving the pilot to do a full NDB at BDG to the min then overshoot due not being visual then off to an Alt AD (ECH) where another NDB was performed & a successful landing was carried out, remember all on one donk! Couldn't think of anything more terrifying. Without being awful here I doubt few could handle that scenario without proper recurrent training to a very high std.in a well maint A/C
Wmk2