OC
why didn't the pilots know their machine and it isn't a problem with the machine
OC, There are several levels of knowing your machine. Because I was mechanically inclined, I got into the maintenance manuals and knew my machines better than most, but that was not a 100% guarantee that I knew what these aircraft were doing at every single moment.
Since then, the level of complexity of aircraft has gone up by an order of magnitude or two. I remember a number of years ago that Boeing and the airlines decided that it wasn't practical to teach aircrews everything about their aircraft and to only teach procedures (About the time that the 747 first came out as I recall). With computerized aircraft and pages and pages of logic diagrams, you will run out of time before you really understand how your aircraft works.
Now take an aircrew that knows their procedures pretty well, put them several hours into a routine flight, then suddenly pull the props out from under them in the wee hours of the night in turbulence. Before they can even begin applying procedures, they need to understand what they are facing. If they begin poorly, they can make seriious mistakes. Do we really need to pull
all the props out?