Interesting summary.
I'll remember [d^2ψˆ ( z ) ]/ dz^2 + m^2ψˆ ( z ) = 0 next time it's rough.
We'll never know if it was over controlling, or controlling and getting out of phase, or just the sheer force of what they went through.
I look back on what I took Shrikes through back in the day. It was years before this accident and Google so I had a deal of confidence (ignorant perhaps) in the airframe. With no radar, you'd look for the tops of the wet season CBs from a distance, dial 200 on the ADF to check, pick a heading, stick to that and wait till you were spat out the other side.