impure or inedible?
don't break the bones of the pesach offering, seems straightforward...
but the tangle of what could and could not be included that ends up weaving all statements together:
not the tail-bone
not if it went out of the boundary
not raw bones
not a bone with only a teeny tiny meat on it
not if the meat on the bone wasn't on the break
not if the timing lapsed...
all make the cracks appear in the simple instruction "don't break the bones"