OK, fine. The next two Amazon books I get for "programming interview", "Elements of Programming Interviews" and "Programming Interviews Exposed", both have three authors each. In both cases, only one of the authors is actually employed as a programmer. The others include an EE professor, a radiologist and two executives. The field is rife with non programming authors.

"I wrote a book about programming interviews" does not signal to me that you are, in fact, a programmer.

I am happy to believe Gayle is a programmer, but I wouldn't use her book as a credential to support that claim.

(And I just realized that I'm replying to Gayle. I didn't read your username before posting. oops. The "you" above wasn't meant to be directed at you personally.)

It's hardly rife with non-programming authors.

Elements of Programming Interviews: authors include an algorithms professor, a software engineer, and an engineer/CTO.

Programming Interviews Exposed: authors include software engineer, a CEO & VP Technology, and a radiologist. (Note that this book was written a long time ago. The radiologist probably was a programmer at the time.)

Ace the Programming Interview: software developer

Data Structures and Algorithms Made Easy: software developer

Out of 9 authors (including myself), 8 are/were software developers or something else very, very deep in technology. Possibly all 9.

Notably, zero are/were recruiters.

What, she's worked a Google, Microsoft and Apple as an engineer. While she may not be currently employed as one, she certainly could be if she wanted.

It is more or less a collection of puzzles used in programming interviews (in that particular book, at Microsoft). He has another titled "Are You Smart Enough to Work at Google?" Similar concept, both focused on programming interview puzzles.

No, they're actually not focused on programming interviews. Those sorts of puzzles aren't asked in programming interviews.