I had it thoroughly whipped into me when I was doing my apprenticeship as a tool and die machinist to notice detail (after I made a tiny mistake that cost my boss thousands of dollars to correct, I never again underestimated the importance of paying attention to detail). It has nothing to do with appearance or fit of parts, (and, this shows up ONLY on the solid gold ones) but, I think I will keep you all in suspense for a while longer... And, while I may not be right (unlikely, but possible), it is connected to other things we have seen on the P2s, and I can think of no other logical explanation to account for what we see. After all these years, there are still some details that have yet to be figured out.
BTW, logical thinking, a skill not widely taught or appreciated any more, has served me well over the decades; looking without seeing, or hearing without listening, can cost you a great deal, or get you into far more trouble than you can get out of...a whispered fact is more powerful and persuasive than a thousand shouted lies (or, it should be, anyway). I accept nothing as established merely because it comes from some "authority", until and unless it can be documented; nothing wrong with speculation, as long as it as put forth as such, and kept within reasonable boundaries...sometimes, even guesses turn out to be right.
We live now in the trailing years of a golden age...not far from the original events, but getting farther away with every passing day. What will collectors a few generations down the road be able to do, unless we sort out as much as possible now, when things are still reasonably clear, and make them a matter of public record?