Wrong, wrong wrong...... Saddle sores have nothing to do with fore/aft position of the seat. Numbness has nothing to do with strength. It is a pinched nerve or lack of circulation. Being stronger will not help with the irritation of the myelin sheath of a nerve. And the safe fore/aft position of the seat has a wide range of acceptable settings. Think of the difference from a tri bike to a recumbant or a laid back geometry bike. As you can see there is a huge range of fore/aft positions..none of which screw up your knees.