Great exercises and like most everyone has said form is everything. I will see this season if this type of training helps my skiing (I am very optimistic it will)
The best book I have ever read has been Becoming a Supple Leopard. It is a big text book style but I have lifted and trained all my life and this author taught me so much I wish I had learned at an early age. It is also a must read in my opinion for CrossFit athletes.