GM advise can be very hit or miss and John Wick's stuff is the same. That being understood, this is one of the best reads I have had for some time. It is witty and clever, some of the advise you can even use. It has been a while since I read a book from cover to cover in one sitting and if I had not had a four year old to deal with, I would have. Excellent book, would recommend it to any referee that is feeling a bit jaded and needs a reboot as an essential read.