Listers,
For what its worth, i find this conversation fascinating and I'm learning a lot. This is far less tiresome than the tail end of the great Bondo debate of the summer of '07.
I struggle (OK, not struggle - more like contemplate over a beer) with these issues when I look at my chrome Frejus with rust on the rleft fork leg. I think that the rust is intrinsic to the story of the bike and I do feel like it is not damaging to the bike, so apart from an occasional oily rag wipe down, I've left it be. I think it gives the bike a certain 'je ne sais quoi', or whatever the Italian equivalent is, but I've built the bike with that in mind... that is -the parts follow aesthetically in that anything I've bolted to the bike has been a bit beat up to match the frame (which actually has perfect chrome from the head tube back).
In this case, the 'patina' is more a mental construct than an actual technical state. I'm OK with 'patina' referring to damage that sheds light on the history of the bike ('this dent came from a crash at the last stage of the '74 Tour', or some such). But I will freely admit that I'm not a scientist, and don't share Dr. H's exactitude when it comes to technical vocabulary - though I respect and appreciate it.
I work in Historical Preservation and this is a 'hot' topic in my field (outside bicycles). To me, the interpretation of the object is more important than the object itself. To walk through a pristine house is to walk through a sanitized past that futilely attempts to refute the ravages of time. The very damage that is reversed by a conservator is the history of the artifact. In my opinion stabilization is the goal, rather than achieving a 'like new' state.
In the case of my Frejus, there's no denying the bike is old, and has had a past that has impacted (patina'd?) the frame (being left in a basement in this case), and I feel that the bike is more interesting as a result. So in my case, I default towards stopping any deterioration and then leaving the bike as is - and I also know that every time I ride the bike I am contributing to it's eventual demise - but also to the history of the bike that started fifty years ago in Torino.
That said, I have seen beautiful restoration jobs, and I am not at all adverse to owning a pristine classic, no matter when it was made pristine.
Loving a diversity of opinion, I am Harry Schwartzman, in Long Island City, NY
Shameless OT plug aimed at NYC residents: If you like traditional jazz, we're hosting the Red Hook Ramblers in Louis Armstrong's garden tomorrow (7/20) at the Louis Armstrong House Museum, 34-56 107th Street, Corona NY 11368 (718 478 8274) - 1pm to 4pm, secure bike parking available - right by Kissena Velodrome.