I suppose I should stop paying for car insurance then, since I never had an accident either. Or maybe more accurate example is that I shouldn't worry about the safety of my car, since I never actually hit anyone with it.

>>How much harm do you suppose it would do, leading to "massive legal trouble"?

There was a cyclist in london recently who ran into a woman on his modified bicycle, she tripped, hit her head on the pavement and died - he was subsequently found guilty of manslaughter and sentenced to prison for many years.

You could run into someone at 5mph, they could hit their head on something and die. There is another case exactly like this going on where a person hit their head on a bollard and left him permanently disabled for life.

The entire point is that if you are on a path specifically forbidden for cycles, and an accident happens while you are cycling, you will be found guilty and will have to face consequences, most likely much harsher than if you weren't doing something forbidden.