Warren in Lancaster, PA
The condition of an old 19th century plane is little indication of how planes were used traditionally. Unless you look at plane irons which you know have been untouched since 1810 or something, you are probably not looking at an iron which has been sharpened by someone skilled in the use of a plane. Most of what you find in flea markets were originally made for carpenters and were later used by farmers, handymen and collectors. Lots have been sharpened by tool dealers who have no idea what they are doing.