there is certainly a theory behind the statement but I doubt anybody worries to much about it … just touch them up with 150 -200 grit paper and  wipe clean   with a business card soaked in carb cleaner .

you can shine them up with  emery  paper  300 grit + …  wipe clean

just keep in mind that  “dressing  points” contacts is a temporay solution  it helps  but they will eventually  arc and  get pitted again…… new  points  are eventually needed. ..

see step #5 in the manual

I had  a Crosby Cruisette …came with  2 bunks  head  sink  water  reservoir   🙂

sold  it to an idiot  who  has let it  soak rain and sun for 20 years .sitting on a trailer.

ran great with just a  Merc Classic 50  but rated 90hp

visit Fiberglassics  for more info on Crosby boats