[nathan_hui]

My interpretation of that rule is that you can use previous concepts, but say you design a chassis that is completely perfect and use it one year. You cannot rebuild the exact same chassis (down to the same exact holes) in each part and use it the next year. One theoretical exception is if you make the chassis COTS, in which case yes, you can reuse the same exact design. Otherwise, you'd have to modify the chassis in some way (which you most likely would given the difference in the rest of the robot).

Simply put, you can reuse concepts, but not finalized designs. You can do general design before kickoff, but you still have to (read should) do some design and modification after kickoff.