Not sure about leaving the roots, but I am at least gonna hang the whole plant next time to slow down the drying process. Last (first) time the humidity was so low, my buds dried in less than 3 days to almost crispy. Granted, they were not so tight airy buds, but they still have the hay smell but its getting better with time. But yeah, roots have no THC but it seems like they can extend your drying time.