I hope to never hear this first-hand. Of course I've increased the
odds in my favor quite a bit by flying a fixed-gear aircraft.

I cannot tell - Was this a pilot mistake or a gear failure?

Pilot mistake... if you read the forums attached to that page you'll
see that they were doing multiple landings with the gear down and
after the previous one the pilot retracted the gear (force of habit
he says) and forgot to put it back.

BTW, the Ground Proximity Warning systems used on transport aircraft, even
25 years ago, were a little more informative to the pilot. Instead of just
a horn or siren, the audible annunciator said "undercarriage" from about
2500 feet agl until a much lower altitude--then it said "UNDERCARRIAGE!"

The warning horn is really just an interruption--in the hope that a pilot
will notice it and investigate.

My reason for mentioning this is that the technology to substitute an
audible annunciator has become extremely light, reliable, and cheap over the
past quarter century. A more informative type of alarm would be very
usefull for those of us who occassionally suffer from "sometimer's
desease"--which I suspect is most of us, if not all.

IMHO, it is time for the FAA to "step up to the plate" in a constructive
way, and provide a blanket approval for an inexpensive conversion based on a
337 form. They should also try to make every IA aware of the availability,
so that the IA can offer it at the next annual.

Just my $.02

Peter