Much like any tablature book on the market, you have to take the info within the book with a grain of salt.
These tabs are not transcribed by the actual musicians, but by people trying to figure out the easiest way to play these songs.
With that in mind - upon viewing the S&M video, I discovered that "The Thing that Should Not Be" is not in drop-D tuning as the book says, but rather in standard tuning tuned down a whole step (much like "Sad but True" or "Whiskey in the Jar" or "Sabbra Cadabra")- as far as I can tell, the only Drop-D tuning song that the mighty metallica does is "-human" from the afore-mentioned S&M.
these books are great to help you through trouble spots when you are trying to figure out certain difficult passages, but nothing beats figuring it out for yourself.
Still... could not have figured out some of the parts from this momentous album without the help of this book (especially considering what a novice I was when I first bought this - remember kids - downstrokes only... otherwise you won't be as cool as your Uncle James)