This is New England, and mostly on granite or other hard stone. You have to use wire brushes, scrapers, and often maddocks to clean routes, and it may have to be done all over again in a relatively short time if the route is not continuously climbed. I'd say go for it, and most of us would be glad, though asking is not a bad idea. It might start a conversation that leads to more information about the route ( it also runs the risk that they turn out to be a crank

). You just want to be aware if you can be of any rare plants in the area to avoid. Blueberry bushes in cracks are not.
If it is a previously established route, you want to be more hesitant removing any rock that would change the nature of the climb unless it is for clear safety reasons.
An example of a NE climb that needs recleaning:

Don't be shy about hitting it hard where you have to, just clean up the mess at the base by the end of the day.