My ideal adjustment is at the very top of the normal post. It tends to sink over the course of my 20 minute commute under my clydesdale frame, no matter how tight I keep the clamp, creating the knees-at-my-ears sensation.

I'm wondering if the wobbling created by the post's long and imbalanced reach contributes. If I used the longer post, thereby grabbing post midway on that shaft, might that help?

Steve M.