If an incorrectly rigged connection is effectively 'jammed' together by
friction, isn't it only going to be detected during a PCC if the load
applied to the control surface is greater than the load required to overcome
the friction?

Very few connections rely on friction. For the H connectors, I would expect
the socket to pop off the ball at at least one of the full deflection points.
After connecting them, try lifting the socket off the ball, maybe?

Be aware that control surfaces are not designed to take high load forces
applied at the surface...doing so might just break it.

I have a written checklist for rigging my glider which
includes PCC and cross checking. However, I've never met anyone else who
does

Pleased to meet you, my name is Jim Vincent. Now you have met someone;-) I
keep my CAC and post assembly checklist velcroed inside my cockpit jsut behind
the canopy. Ready for access every time I rig. I figure the more idiot proof
I make it, the less I have to worry about what I might have missed.

Jim Vincent
N483SZ
illspam