I've read the Collars book.
The book describes a method to hedge your portfolio using puts and a ratchet. As it is, the method is slightly above mediocre, the plus point is that you won't take a big hit
If you are able to time the market reasonably well, then the method has potential as you can tweak the collar entry to raise the ratchet, and the tax saving is huge. I used it in 2013.
There is a thread about the book in this forum.
I made a post somewhere about courses which were value, search thru my past posts to find it.