What's good about the toilet is the flush completely rinses the
   shampoo clean. _supposedly_ the cold rinse is better because it
   closes the pore that the warm wash water opened up. Supposedly
   also true with 'sealing the hair' in some way. I suppose there's
   some truth to it. Hair's mostly what, silicon? And silicon
   reacts to cold by its molecules coming closer together, and
   silicon which has closer together molecules will give your hair
   a nice sheen. So, might be true enough. Then again, I could be
   completely and utterly wrong.