Sydenham High Street probably demonstrates the workability of the "shared spaces" thing. Even with the kerbs down, the boundaries seem to remain. I could be wrong, but from my own experiences down there, its not been a problem. I can see where the concerns lay, however I guess one why to look at the lowering of kerbs, is there is no high revving and lurching forward as people try and swing into a tight parking space.

Not sure who first came up with the idea of losing the kerbs, but I can see it from both sides.