Jeeze, Flecc. A cyclist could just as easily hit a curb or brick wall in some circumstances.
They are more dangerous than that though, and I don't like the way they take up cyclepath width. In London commuting cyclists are overtaking slower ones all the time. With these cyclists have to conform to the slowest one or they make a potentially dangerous overtake in that confined width. The slightest nudge in passing someone within that width and one hits the obstructions.
Another common problem in London is the pedestrians suddenly stepping off the kerb ege without looking, even to pass others on crowded pavements. These obstructions leave no swerve room.
You might find them acceptable in Sleepy Valley, but here, no way.
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