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
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