Is it groundhog day? I swear I read this before.
I never had BTS on my Raichles and when I switched to UPZ RC11, I was shocked by how much they flexed and soon ordered the orange race springs to help stiffen them up. I proceeded to add a lot of preload to the orange springs as well... I've since been backing off the preload to get them to flex more. I no longer feel that they are super flexy.
I was running max forward lean in my rear foot, and considerably more upright in my Raichles.
Once your foot is in the liner and boot, you can't lean back to let everything close up? The liner can't be that stiff to prevent you from pushing your calf back into the cuff?