Originally Posted by
jtgotsjets
... the seat would stay in the same relative position over the post, no? ...
No. Assuming the clamp attaches to the rails at the same spot, then having the clamp in in front of the post puts it about 2" forward of where it would be if the clamp is behind the post. The length of the rails on your typical saddle allow for about 1 1/2" of adjustment.