Originally Posted by carleton

Any pics (even product pics from the website) of the seatpost in question?

This is a common problem among clamps that use a one-bolt design. They seem to work based on friction. These work fine when the rider is in the center of the saddle. But, if one rides "on the rivet", it's subject to tilt...even under smaller riders.

This is why 2-bolt systems (like Thomson and many others) are prized. The bolts work in opposition of each other, one keeping the other from giving up.