I think I might know the answer to this, although this is just a guess. It's a bit too subtle to tell this from the photos, but the paint along the top tube of my bike has a slightly matte quality compared to the glossy finish on the rest of the bike. I was mystified by this at first, but when I learned that the bike was built specifically for the bike show, with the intention of Eddy Merckx signing it, I figured that the workshop prepped the paint on the top tube to make the signature take better.
Gene Balk
Seattle, WA
>>>>>>
>
> I had Giovanni Pinarello sign the top tube of my Prince frame when I
> purchased it in Italy in 2000, using a black Sharpie(r) I had with me at
> the time. I also covered the signature with clear Mylar(r) film after I
> had the frame back home. It's now 7 years later and the signature has
> faded to brown, and will likely fade away completely some day. Why does
> the signature on the Merckx still look so good?
>
> Wayne Bingham
> Lovettsville VA USA