Steve : I offer my solution , not theory, I bought a QR seat post band clamp .
the same size as the seat post itself.

then I took off the inside lip on what would be the band's fitting on the end of a frame's
seat tube , until I could just slide the band QR over the seat post ,
it now sits upside down on top of the frame 's QR..
to fold I just open both QR's ..

the one on the post itself slides up the post ,
then, when I pull up the post again , I slide QR No.2 down and clamp It there ..

If you are going to buy another seat post , consider the telescoping one ,
it will not stick up quite as far as the extended one , when folded
and if you are packing it you can always take out the upper section of the telescoping one.. with the saddle.

I got the rubber Bung for mine so the end of the post will not dig holes in the nice
(hardwood?) floor or grind/ chip off the end of the post if pushed into the pavement.


there are still the TI seat posts optionally ? are there ?