Sadie Kate I WAS WRONG!!!
(I knew I shouldn't go by memory...)
I quote from Long Distance Cycling:
But in terms of knee problems, two points are worth emphasizing here. First, a saddle that's too low creates excessive knee bend at the top of the pedal stroke. This can result in strain or damage to the patella tendon. Second, a saddle that's too high creates excessive leg extension, which can put undue stress on the tendons and ligaments behind the knee. Hence, Andy Pruitt's simple maxim: If your knee hurts in front, raise the saddle. If it hurts in back, lower the saddle. In addition, work to develop a smooth pedaling style. Ragged leg action increases the strain on tendons.
Sorry...