Addendum: Depending on how one draws the boundaries, I myself may be on the wrong side of the "stewardship" relationship with at least some of my bikes. There's a fine line between "enhancing" or "upgrading" a bike and destroying its history, and I'm not even sure myself where some of my projects fall within that spectrum, or if it even matters for some of my projects. Some examples:
Motobecane Grand Tourings: The paint and graphics will be kept stock. The drivetrains will be modified from 10 to 15 speed. This was a period-correct upgrade, however. I also plan to add fenders and racks-- again, period correct. The bottom brackets will be replaced with Phil Woods, and the auxiliary brake levers will be replaced with guidonnets (if it worls aesthetically). The paint will be touched up with automotive paint. Enhancements? Or destruction of the bike's history and context?
Fujis: The Allegro will be rebuilt as a fast road tourer. The hi-ten fork will be swapped out for a Valite fork. The underlying gold paint will be kept, but I am changing the trim from brown to red. Components will be upgraded in terms of quality and contemporary performance. Wheels will be changed from 27" to 700c (I don't want Ms. Blue Order to have to struggle with odd sizes). The Sagres will be repainted blue, Ms. Blue Order's favorite color, with gold trim. I haven't quite decided how to build the Sagres, but it will probably become a city bike, again with 700c wheels, and with flat bars and upgraded components. Enhancements? Or destruction of the bike's history and context?
Gitane: My commuter, the Gran Tour will be kept mostly stock, except for the simplex barcons, which I'm not having much luck finding, and which will likely be replaced by SunTour barcons. I also plan to add cyclocross interrupter levers, and change to aero levers on the drops. Enhancements? Or destruction of the bike's history and context?
Trek 850s: These will be powdercoated fluorescent green (stock color is yellow), and stock decals will be commissioned and applied. The under the chain stay u-brake mounts may or may not be replaced with seat stay cantilever mounts. The cable guides will most likely be cut off and relocated to the top of the top tube. These will be rebuilt with mostly contemporary touring componentry. Conversion to touring bikes? Or destruction of the bike's history and context?
Raleigh Portages: These will be powdercoated white (stock color). The head badge decal will be replaced with a brass head badge. Only one of the decals will be reapplied. Componentry will be upgraded. The mixte is actually newer than the diamond frame, so I will be replacing the fork and the bars with a fork and bars that match the older of the two Portages. Enhanced? Or destruction of the bike's history and context?
Trek 830: This will be my winter commuter. Cantilever posts to be cut off and replaced with disc tabs on fork, and an internal hub on the rear. Enhancement? Or destruction of the bike's history and context?
Raleigh Record: My fixie bait. Unless I find one in bronze green, I may paint a blue one bronze green, with appropriate white trim and correct decals. The fixie conversion itself will not alter the frame in any way...with the exception of the bottom bracket threads. Destruction of the bike's history and context? Or acceptable period-correct alteration?
I use these examples to illustrate my own dilemma when confronted with my own words. How much change to a bike is "too much"? How much change exceeds the permissible bounds of good stewardship? Why is it OK for me, for example, to relocate cable guides on my Trek 850, but it's not OK for somebody else to grind his cable guides off? Why is it OK for me to powdercoat my Trek 850 a different color, but it's not OK for somebody else to powdercoat his uniquely-colored classic bike white? My point in raising these questions is that there's not necessarily a bright line between permissible changes and violations of the trust we keep. Or maybe there is, but we excuse our own follies more readily than we excuse the follies of others. Is "destroying" a bike's history like Supreme Court Justice Potter Stewart's definition of pornography: "I know it when I see it"? Or is there a readily definable line beyond which the "owner" of the "personal property" should not cross?