Got a good chuckle out of that, Bulgie! My bet is that it will work particularly if the extender is thick enough to handle lateral forces. With three points of securing the extender to the fork blade it is unlikely to fall off.
Like Andy, we used angle iron to convert our Stingrays to choppers. Billy Martis extended his blades out 6 feet and rode it for a full semester like that. He went on to become a really good...nope, not engineer... guitar player!
FWIW, make the stuff from steel plate.