I guess the readers of the thread can make their own decisions, as you have, about what extent they want to go to when removing fat and meat. I have been a professional taxidermist for nearly 15 years, and have probably done hundreds of birds/tails over the years. My professional advice is to clean them so there is nothing there to rot. No one has to take my advice, but those that do will be happy with the results, and can rest assured their mount will not attract the dermestid beetles that can destroy other mounts, as well as clothing and furniture. I like a little peace of mind.

If you are not worried about carpet beetles, or don't mind a temporary odor from the rotting fat, then by all means take a shortcut and just do the bare minimum. Everyone gets to decide for themselves.