Yes, cords CAN be less than a foot. Remember they are just extensions of a longer cable. Also notice that I said UL certified cables. They need to be used as normal cables also, and normal cables cant be shorter than 3 foot.
Anything longer than a foot will hold a signal. Anything shorter will fail when hooked up device to device. Going from a patch panel to a hub is a whole different story.
Did I confuse anyone with this, lol?