From: "Roger Wesson" wikipedia@world-traveller.org Not sure that changing distances on road signs would be that difficult or at all dangerous, it's just that being on an island we have no compelling reason to conform to the continental standard - there would be no benefit to be gained from a switch.
Hmm. Well, using the Canada example again, it shares a continent with a huge neighbour that uses miles, yet it apparently found a compelling reason to switch anyway.
Jay.