If you buy high quality coffee and prepare it in a gentle and controlled manner, adding salt to it will likely make the experience worse. For everyone? A pinch could be in order.
One of our favorite coffee gurus (and maybe yours too), James Hoffman, explores the science on this in the video below.
He explores how a pinch of salt can remove the rough edges of a less than perfect cup of coffee and balance the flavor. Why does it work? Because a good cup has the right kind of bitterness (not the type of truck urn ground in an unwashed truck).
Aside from an interesting science lesson, the video is worth seeing just to see poor Hoffman making his way through cups of salty instant coffee.