I particularly dislike the color of paint comments. One-hundred-year-old paint is not the same paint that was originally applied. Even if covered by more paint or hidden behind a board. There are subtle changes in the chemistry which equate to color change. Many painters made their own paint. Yellow ochre comes to this day in many shades of yellow to brown. So, the ocher you use today to make paint will most likely be different than that of the next year. And to top it off, very few people who are alive today were alive when much of the painting was done the first time and didn't pay attention then.
Paint is a thin layer of stuff typically for visual purpose. When I hear “wrong color” I think "well next time we will try again". It isn’t like we got the architecture wrong or removed a wheel set or cut the smoke box off. It is just paint.
Paint experts really annoy me, don’t contribute to the program and are generally useless. A historic paint specialist is, however, can be a truly great asset.