The reason futures truth single out that faker Covel is that he has been taking newbies for years with a substandard version of the (available free above) turtle rules. He has then disappointed them with his support for their questions.
He couldn't trade so he sucks newbies in instead. His web-site appears good on the surface but uses large amounts of information to hide a few deceptive lies that further his aims.
Out of sympathy for the people he sucked in I would never buy one of his books, let alone anything more expensive (note that simple turtle trend following has not been working well over the last few years and may never work again).