Originally Posted by
spock
People with short torso and long legs would benefit from being seated more to the front with road bikes. Also, if the bike is more of an upright seating type like a hybrid. Basically, it's all about the balance of your upper and lower body in relation to pedals...
This describes me, too, and during a professional Guru-system fitting this spring, the fitter had me switch to zero setback. He did, however, emphasize to me that the decision was based entirely on my personal measurements compared to my specific bike, not some universal factor favoring that type of seatpost.