Quote: " I see no significant difference in the pitch torque generated
by a T
tail and a conventional tail (apart from a minimally longer arm for a T
tail on a given typical glider design).

"Am I missing something?"

Yes. It's not pitch torque that is the issue. It is the torque on the
fin/fuselage junction about the glider's longitudinal axis, caused by
asymmetric and/or inertia forces of a tailplane mounted at the top of
the fin - maximum moment arm. That is much greater than from a
tailplane on or close to the fuselage level where its moment arm is much
less. I had a share in a T-tail glider where the fin/fuselage area
delaminated during a final glide with violent oscillations of the whole
empennage before the pilot reduced speed and landed safely.

Chris N.