The Muffler was the reserve of the working man, usually employed in heavy industry.
Mens shirts were on the whole collarless. Any collar could be attached by two shirt studs which passed through button holes on both the collar and the shirt. Men who wore them, would attach a fresh collar each day but only change the shirt perhaps once a week. Working class men might only wear a collar on Sunday when they donned the fresh shirt for the week. The Muffler either simply crossed or looped like a cravat, was worn for warmth and appearance over the collarless shirt during the working week.
You may see mufflers tied in a loose bow, I imagine these would be more flambouyant characters such as dockers, market traders and porters.
No office or shop worker would be ever likely to wear a muffler.
Photographer: Alun Edwards The Grove Aberfan A very small Welsh coal mining village
It would not take a genius to work out that that the man shown here is most likely a collier.