I saw that bit of the prog.
On a similar theme I heard an American chap interviewed on the radio a while back who was totally blind and had taught himself to get around by echo location. So successful is he at doing this he can detect small item across a room, and even differentiate different textures of floor/road surface, even to the extent of picking out cracks in the pavement. More amazing yet is that he rides a bike, in traffic. How he manages to hear his on clicks echoing back to him I don't know but it seems he does.
Further than that he rides his mountain bike along trails and forest tracks with no bother at all. I understand these aren't tracks he knows off by heart, all tracks, any tracks.
He lives alone, out in the sticks.
If I remember correctly he teaches his skill to others as well.
