Originally Posted by
genejockey
You raise a DIFFERENT question, which is the degree to which ankling changes the path of the pedal top. On average (I found) riders' foot angle changes 24 degrees from minimum to maximum deflection. Look Keos have a stack height to the top of the pedal of about 11.5mm. You can determine how much this would move a point on the pedal top with some simple geometry that I can't be arsed to bother doing. Knock yourself out.
A quick calculation shows this effect would result in a deviation from circularity of less than 1.5%.