Ian Smith wrote:

On Mon, 23 May 2005, JNugent wrote:
Mark Thompson wrote:

I think he mentioned them as a way of highlighting the idiocy of
banning a unicycle...

Why?
Do rucksacks also have hardened steel sharp bits sticking out and/or
covered in black grease as well?

As well as what?

As well as cycles.

None of my rucksacks have hardened steel sharp bits sticking out
(unless, I suppose, I put a hardened steel sharp thing that's too big
to fit entirely inside partly within the rucksack).

Good.

Neither does my unicycle. Nor is it covered in black grease (or any
other sort of grease). There's a small amount of grease sealed within
the pedals, and an even smaller amount sealed within the cartridge
bearings.

The tyre, pedal ends and seat (ie, all extremities) are all black
rubber, so not liable to scratch dig or gouge anything.

....but still containing enough road dirt to be easily able to foul the
clothing of an adjacent passenger, perhaps on their way to a night out?

Whatever your views on where the balance should be struck between the rights
of cyclist passengers and the rights of pedestrian passengers, you *can* see
why bikes (and, if appropriate, unicycles) are banned on the Underground?