Pete Owens wrote:But it doesn't mean it is illegal for pedestrians to walk on the part designated for cyclists. The law does prohibit cyclists riding on the pedestrian bit (just like any other footway), but not vice versa. Fortunately, although the sign is circular (generally indicating compulsion) this is not the case with this one - or indeed the blue circle with just a cycle in it. We are still free in this country to ignore the c**p and continue riding on the carriageway.
I think there is a widely held misconception about these blue signs. (I recently saw a letter to a paper which made the same mistake, claiming that blue circles with cycles in many that use for cycling was mandatory.)
The mandatory aspect is not that certain users must use them, but that others must not. This also applies to "mandatory cycle lanes": it is mandatory not to drive in them, but it is not mandatory to cycle in them.
In other words, and this is the easiest way to think about it, there is no mandate that applies outside of the signed lane or track. So people are still free to cycle on carriageways, to walk on carriageways and cycleways, and so on (motorways and TROs notwithstanding, of course).
The signage and the wording could perhaps be rather clearer, but they remain mandatory.