Without the restriction being discussed how does the club/insurance company
control which pilots are risking the airplane?

"Risking" the airplane? What are you talking about? The PIC "risks"
the airplane every time he flies it. He "risks" the airplane even more
if he takes a passenger. Perhaps passengers should be required to be
club members.

Without the rule a club member can designate any warm body sitting in the
right seat as safety pilot.

No, the safety pilot has to meet certain FAA standards. The PIC "risks"
the airplane every time he puts on a hood. But it is the PIC that is
risking the airplane.

The rule seems to head off the ambiguity by
requiring both pilots to be approved by virtue of membership.

Ambiguity can also be headed off by requiring all occupants to be club
members.

Jose
--
Humans are pack animals. Above all things, they have a deep need to
follow something, be it a leader, a creed, or a mob. Whosoever fully
understands this holds the world in his hands.
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