showbo:
Correct...... but I seriously doubt the NTSB will ever conclude that the crew didn't understand this. Nor that they didn't know they were supposed to sequence the FMC and "extend" the approach; nor that they didn't know that the autopilot was supposed to be disconnected by 50 ft below the MDA; nor that they didn't understand that 1500 fpm at 1000 ft afe is an unstable approach requiring a go around; nor that they thought the "minimums" and 500 ft callouts were optional. The question will be, what human factors caused them to make all these omissions?
I don't believe there is sufficient information to conclude that the crew didn't understand the PAPI requirement. But, their actions make it reasonable to conclude that they disregarded this and the other visual cues requirements of FAR 91.175. Similar reasoning applies to the other omissions you cite.