This is simply whisky and water, but as with the Japanese tea ceremony, observing the time and care taken over it making and the prolonged anticipation...
This is a great way to enjoy fine whisky (or whiskey) without getting too f****d up. It might seem sacrilegious to dilute something you may have paid $200+(++) a bottle for to that extent. But if that bottle truly has the character that you paid an exorbitant sum for, it will shine through in a Mizuwari.