shared-use paths for pedestrians and cycles are dangerous, for both cyclists and pedestrians; indeed there is research showing they are more dangerous to cycle on than the road proper. If you cycle much faster than walking pace, there is a risk of collision with pedestrians who meander across the shared-use path as if it were a pavement

I agree. I am often confused by shared-use paths. And I have pretty good sight (in broad daylight). I don't think I've ever met a shared use path with a tactile and fluorescent band between the spaces. In such confusion, it's the pedestrians who suffer.

And nothing can EVER justify riding on a non-shared path, apart from needing stabilizers and not having anywhere else to practice.