That chart has been around for quite some time, usually as a poster-sized wall hanging for machine shops. It's impressive what an experienced mechanic or a machinist can figure out just by looking at a worn or failed part. I'm working part time as a warranty claims inspector, looking at and photographing damaged parts for several extended warranty companies. Then I file a report and upload the pics to their website for the adjusters to evaluate. It's an interesting way to make a little extra pocket change!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!