I think they meant the pedals (with your feet on them) at 3 and 9. If you look at the crank arms like a clock, that would put one pedal forward and one pedal rearward, with both pedals being at the same distance from the ground.
Um... "Stand up with your feet at 3 and 9 o' clock"? That's doing the 'splits,' and your legs would be at a 180° angle parallel to the ground. I don't think that can be done while standing up! Did you mean something else?