Even a helpful book like his short selling book is not worth much, in a bull marke//uptrending market,,especially since 2014 is about 50% gone.Sell in may + go away is not a prediction, nor is a 200 dma or 50 dma.The latter moving avereages were explained/pictured/charted in Williqm O Nelll's books, maybe not helpful @ all to some seminar.
To reiterate:
As to what it's worth in 2014, I have no idea. As I said, I hadn't looked at it in decades, and I haven't traded stocks in 15yrs. If you trade stocks, it may be worth as much to you now as it was to me back then.