This is a clear example of me ignoring my own advice. I put forth a very similar hypothetical scenario recently on the Auburn restomod thread. This Gios was sold as a frameset in 1983. I can easily imagine someone buying one and building it up the next year with Dura Ace 7400. Then eventually it would come into the hands of someone who would correct this mistake and install Campy components. Let's say that happened in the late 90's. Would they replace the DA 7400 stuff with friction shifting? No way. So now it's got probably 2x8 Record or Chorus components. Eventually the owner finds himself having become an overweight middle-aged man and he looks at the latest Campy Racing T offerings.

Quod erat demonstrandum

Thanks to everyone who participated in this discussion. Against all odds, it has been very helpful.