Demagnetization for MC - good or bad?

Over the years I have always used the Aesthetix MC Demagnetizer on my cartridges as a matter of course but must admit I had never identified any audible improvement afer treating the cartridge. I recently installed a Benz Micro Ruby 3H on the LP12/SME 309 combo and made an inquiry to Benz as to their opinion on demagnetizing. Their response was that it should never be done as, in their words, it "weakens the magnet". Would anyone care to comment on this situation?