Larry Dighera wrote

Another question that no one seems to be asking is, what
prevented the pilot and student from employing their parachutes
as would be expected?

Getting out of an airplane with a parachute was difficult enough
that the Navy required us to complete a "bailout" training program
using a T-34 bailout trainer. It consisted of the fuselage and
no wings but a lot of foam stuff to land on. The engine was running.
Not a simple task even considering that the trainer was static.
I have a hard time imagining someone (trained, or not) getting out
of an airplane with one wing missing doing it's death gyrations.
If you track the survivors of damaged aerobatic aircraft, you will
find very few who successfully bailed out even though they were
wearing parachutes. I know of only one airshow pilot in recent years
that completed a successful bailout.
FAR 91.307 is nothing but a big farce. I strap a parachute on my 70
year old neighbor and go out to enjoy some acro in a YAK-52, now we
are perfectly legal, but what are his chances of using that parachute
if required?...I'm not even required to instruct him on the location
of the rip cord! I'm not sure that I could get out of an airplane
gyrating with one wing missing, the forces encountered might even
prevent one from raising his arms to open the canopy.

Bob Moore