Thanks for your response,
Well, the only examples we have are the Netherlands and possibly parts of Denmark.
Certainly, separate infrastructure has played a part but there seem to be other reasons.
In Holland, it's clear that housing density and road structure play a part as does a much deeper cycling culture that's significantly different to ours. It's also a classic mistake in programme management to think that you can just lift and shift a solution from another country, organisation, or culture and expecting it to work.
My point is about "infrastructuralists" obsession with infrastructure as the only answer to the challenge of getting our country cycling and their dismissal of other views.