@mchill If the book was so fantastically good as to be worth $100 then many people would have purchased it and it would be a bestseller - even at that price.
Therefore I can only assume the answer to be , no it is not worth $100

@Duchess64 I think you have missed the point of my post. In golf, if a driver came along that was guaranteed to give you an additional 25 yards/metres and went straight it would fly off the shelves no matter how much it cost and who made it.

If a chess book was so good the same would apply. Therefore I am not saying it is not any good because it is not a best seller. Rather I am saying the opposite.