There are many circumstances in which 100mph involves no real risk to anyone, and it should not be illegal. There are others (last time I came back from Nottingham) when the visibility and road conditions are poor. It was pissing down. Lil old petrolhead me was doing about 50. Everyone and their dog was charging past at about 70 or so. Unsafe - but in accordance with the speed limit.

Exactly Richard - that is the whole point. It's driving intelligently in accordance with conditions that makes for a safe driver. You sound like you are one, and I would hope that I measure up as one, too.