>what happens when the magnet becomes deplolarized? I guess then you try the same thing floppy disk rescueing programs did : keep attempting to read it until y

>what happens when the magnet becomes deplolarized? I guess then you try the same thing floppy disk rescueing programs did : keep attempting to read it until you have enough data to make a stastistically significant bet. It should work pretty well since you get an analog value encoding a digital one to start with.