Let me understand you. One hour is all you need to
transition a pilot
unfamiliar with an IFR certified GPS and dual-axis
autopilot into an
aircraft equipped as such? Really?

Really. After all, said pilot has clearly been flying without these
things and doesn't need them. Thus I see no reason to cover the full
functionality of the devices unless he wants me to. He can read the
manual and figure it out himself, we can talk about it on the ground if
he wants to, and if he wants we can work on them - but knowing how to
use them is not a requirement for a checkout.

Would you require a VFR-only pilot to learn how to shoot an ADF
approach just because the plane he is renting is equipped to do so? Or
would showing him how to tune in a station be enough? How is it
different if he's IFR rated? Suppose he's IFR rated but not current?
Suppose he's only out of currency by only 3 months, and could shoot 6
aproaches and a hold with a safety pilot and suddenly he's legal?

Would you require training in LOP operations just because the plane was
equipped with engine analyzer and GAMI's, or would the "Lean to initial
roughness, then enrich to smoothness" be OK with you because it still
works?

Would you require training in aerobatics just because the aircraft was
capable of them? That would make a hell of a transition from a C-150
to a C-150 Aerobat.

There is a huge difference between being able to fly to the capability
of the airplane and being able to fly the plane reasonably safely.
Being able to fly to the capability of the airplane is something we
should all aspire to - but it's not realistic to require that for a
rental or club checkout.

If you could, what is your syllabus?

GPS syllabus - how to put it into direct-to mode and change range on
the map (if there is one). Takes 5 minutes max.

Autopilot syllabus - how to engage heading hold and altitude, how to
disengage, where the circuit breaker is to disable it. Takes 5 minutes
max.

Sure, there's a lot more functionality there - but the pilot doesn't
need it, so no point requiring him to learn it.

Michael