For those still insisting on the "I know it when I see it" distinction of MFDB image quality, I recommend reading Carl Sagan's Demon-Haunted World. While not about photography, the book vividly portrays the dangers of blind faith, and benefits of the scientific method.
Michael's closing paragraph does offer some much-needed perspective, though:
"In the case of horsepower vs. torque I just decided to get in my car, drive away, and simply not worry about it for another moment. In the case of photography I'd suggest closing the screen you're reading this on, grab a camera, and head out and do some shooting. Let the nattering nabobs of negativity natter away. I'll be out shooting and driving."