3-1/2" Floppy Market Cornered

"360K" diskettes are 300 Oersted. That is a measurement of magnetic coercivity. If you have no idea what that means, think of it as being like film speed in photography. "1.2M" diskettes are 600 Oersted. That is way too different from 300 Oersted for interchange to work in either direction with "360K" diskettes. "720K" 3.5" diskettes are 600 Oersted. "1.4M" 3.5" diskettes are about 750 Oersted. 600 and 750 are close enough that you can almost get away with it. You can turn a good diskette of one into a crummy diskette of the other. What part of that is hard to understand? I especially liked the old ads for the punches, particularly the ad where the guy could "PROVE" that the diskettes were the same, because he had measured them with a micrometer. Fortunately, there is no damage that formatting can do that can't be undone by bulk erasing.