I do not think the bnz/40 is necessarily fake, matter of fact I tend to favor the probability they are real, though there are valid arguments for and against the variation. I think Mike did a good job explaining the arguments, as i recall he didn't feel there was enough evidence to call it either way, and left the question open, which was proper on this subject. (we need more & better examples, the same old song...)
As for Backbone, its still worth owning, the datasheets are almost all flawed, - though I tend to look at them as snapshots, not "biblical" (some stinkers made it in too) - the general text i think is good, well written, the main flaw with the books is the limited pool of rifles to form conclusions, which was hardly the authors fault. For those that weren't collecting or familiar with the technology of the late 1980's-early 1990's, communication/travel was a lot slower, costly and unreliable. Today's technological advances over the last few decades are grossly exaggerated, there is far more that is worse than better by comparison, but communications, both in access, speed and cost, is vastly improved. Law & Jensen had no control over that and they did a very good job with what they had, - plus Jensen is a gifted and articulate man, he writes simply (the best authors do, they do not overpower their audience with elaborate verse to be clever, making the the read easier for the casual reader), but he actually edits books, and i have seen his work, - which is first rate. (he is also a gentleman like John Wall was, like many of the old New Englanders, unassuming and gentle in their editorial advice, - he does his best to not to offend! Which is not always so common today, some editors like to be critical in their editing, harshly picking apart your grammar and construction, which might be the best way to make a "student" remember/learn, but it is a bit discouraging...)