My only reservations about the Black Book, is how it appears to be overly verbose. I remember mentioning to Mark Edwards a couple of years ago, when he asked for suggestions to make his product better -- I had mentioned to him that quantity isn't everything, without proper editing. Back then, I had found that he said the same thing over and over using different language and it was left to stand -- it looked like unnecessary page-filling.
I remember liking the Red Line Report on this aspect -- Woodlief is a wordsmith, concise but so effective, using language economically but efficiently.
And didn't like the fact that in the Black Book, there were so many superlatives being used for so many players that it became an annoyance when trying to lift language that clearly established a player's superior profile over say someone within a given tier and even between players ranked far apart.
That said, it doesn't take away from the sheer mountain of facts and data points provided. It's just that Edwards' idea of writing a guide is having you, the reader, act like an editor to weed off the excess. I hope his guide has gotten better in this regard.