I guess that's kind of an experimental test case where the exact same piece of art was published first based off of a black and white version, and second a colored version? (If I read your correctly). So, you are saying there'd be a certain market preference for the black & white version (pencil and ink) vs the colored version.
I would also expect this to be true for someone who asks, say, Laura Martin to color an original pencil and ink page. Even though she may be one of the best colorists in the business, and may do a superb job, it still lowers the value of the art in the hobby.
What I was referring to, however, was when the original art is in color. I should think that the Punisher cover paintings by Phil Zimelman over Mike Zeck pencils, to use an example, are no less desirable or valuable to the hobby collectors, just because they were painted in color.