Just saw a youtube vid from Ron Marsh,who is a N scaler It is a mush watch, for years model railroader have been using all types of things to clean track. Mostly bad to very bad. Rons train and things RTNT is his channel.
While this will only work on the center rail, for 3 rail layouts. most issues are at the point where power is picked up by the roller on the center rail.
WATCH IT and let me know what u think, BILL