I've also got a background in aircraft maintenance- - - -USAF electronics tech for about 8 years. There were some pretty strict rules about reusing fasteners, particularly for the jet engine mechanics. It makes sense that after thousands of heat/cool cycles, a head bolt or main bearing bolt might not do its job as well as when it was new. Toss in a rebuild or three, and those torque-sensitive bolts just might not be as good at doing their job as when they were new. Some modern engines use "torque-to-yield" bolts which can only be tightened once, then discarded the next time the engine is rebuilt.
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!