So, say that some Garmin GPS is ICG-compliant except for the barograph
function. Could not such an FR be approved by the IGC GFAC committee with
the restriction in its approval document that it could not be used for
height evidence?

No, since pressure altitude recording capability is a non-optional
requirement of the Technical Specification (see sections 2.4 and 2.6.5).
In any case, I believe all FAI badge-related flight performances
require altitude evidence, with the sole exception of the 5 hour
Silver/Gold duration.

Marc

Okay, then the solution to the regulatory barrier seems to be to broaden
the Tech Spec for COTS GPS units by enlarging the list of functions which
are optional. If COTS are deemed to be"a good thing" for the vastly larger
population of badge pilots vs record-seeking pilots, then the IGC/GFAC
committee ought to be finding the means to add a few "almost-compliant"
FRs to the approved list (how it can be done vs why it can't).

Of course, there's nothing in the Sporting Code that requires flight
evidence to come from one piece of equipment, otherwise we wouldn't have
cameras/baros.

Regards

--
Tony Burton