Bill,
I don't think you are wrong about "bringing back" a well worn classic, be it gun or auto. It is a matter of personal taste and values. Please do it when, in your own judgment, it seems truly necessary. And of course the threshold is a subjective thing.
The wisdom of such an undertaking should also be judged by how the restoration is to be done. In the past, the origin of this worship of total originality related to the fact that almost all refinishing was poorly done, with too much buffing which rounded corners, removed markings, and generally ruined the gun. That is not unavoidable. It's about skill and the craftsman's approach to what he does. There are some master restorers on this board. They produce art. It has value, in my opinion great value.
In the collector world, collecting anything, there are people who are rigid in their thinking and insist that the firearm has lost most of its value if it is restored or refinished. This opinion is nothing more than that, opinion, with no justification except more opinion, at least in my view. It's "well, somebody who's an expert says..." ...so John Doe decides he must think the same thing. In heaven's name why?
I love this purist point of view and encourage it. Really. Because the worship of cosmetics puts many fine firearms within my financial reach. And I will indeed restore them, if sufficiently worn. And cherish and enjoy them. I could not care less what a rigid-minded collector "thinks" they are "worth". Most of the firearms buying public rejects this purist point of view, completely. High prices for carefully refinished Lugers (and Corvettes and everything else) reflect this reality. Go to any gun show and price a Luger which is pristine, except for having been carefully and professionally refinished. Try to buy it at a $400 to $600 "shooter" price, as purists insist the market to be. You will be laughed out of the hall.
That said, if those who fancy themselves "serious collectors" are willing to pay astronomical prices for totally original guns, that is fine also. These are the folks who will never shoot them and who will give them ultimate care to keep them in this condition for posterity. All of that is good. But living in the real world is more fun for me, and it involves less painful intestinal knotting and contractions. And I don't agonize over electronically controlling humidity and maintaining a calendar schedule for wiping guns with silicone clothes...once I have fully researched exactly which ones to buy.
There is room in the boat for everybody. But the notion that it is a travesty to restore a cosmetically worn collectible gun or Corvette is malarky. It's all a state of mind. Those who disagree are never able to explain exactly why it is so important. They just keep insisting that it is. I say, If something is broken, you fix it. But you should not cobble it up. And yep, all of this is only my opinion also.
What I hate to see is when a truly fine, original gun accidentally comes into the hands of somebody who has no clue as to what it is, and how or why it should be preserved as a collectible. This happens all the time, usually through inheritance, etc. It behooves all of us to intervene, when we can, and try to steer such collectibles to those who know and appreciate them, who will care for them, and who will try to pass them on to somebody who feels the same way. Nope, I would not refinish one of those Lugers, or sell it to the guy with more money than brains, who plans to weld on a highly "tactical" ten inch flash suppressor, or convert it to .40 S&W.
No offense to all you Serious Collectors on this board. In fact, I'd like to help you get rid of those no good, refinished, or worn finish Lugers which have been forced upon you in trades, etc. So to show that my heart is in the right place, I'll make a standing offer of $400, the "shooter value" you talk about, for any original Luger which has matching numbers, is complete and functional, has a good bore, but has either been professionally refinished without rounding corners and removing markings, or else has some bright metal which could benefit from refinishing.
I doubt that my In-box will be flooded with offers, but hey, I could deal with it.