I read The Harbinger a month ago, and am just about to read the followup on Shemitah.
I was quite amazed at what he presented - now I am pretty nervous about investments. I went to see my investment guy to move everything into something secure, but he assured me that 2015 was looking good. I am having second thoughts again.
Having published a book on the Sabbath year seven years ago, I can say with reasonable certainty that Cahn is clueless about how the Mosaic Law was supposed to work. There was nothing mystical about it.