I have short legs and a long body.

In order to stand over my bike, I ride a frame one size too small.

In the case of my Pista, a professional fitting revealed that a 35mm setback seatpost would properly place me over the pedals and the bike in general.

On my Karate Monkey, with 175mm cranks and a Cane Creek Thudbuster, I ride one frame size too small and everything fits without a setback; but then, the Thudbuster tends to place the saddle a little further back than a normal seatpost would, and the Karate Monkey has a more relaxed seatpost angle, and so, when extended, the seatpost goes further back than on my Pista.