This is a very new and undeveloped thought, that's hopefully worth exploring. The thread about HATOs parking on hard shoulders set me off on a bit of a track. See:
http://www.safespeed.org.uk/forum/viewt ... 8990#98990
I realised that we're talking mostly about drivers avoiding crashing by ensuring that they can stop in an appropriate distance and by proper vigilance. But there's a fundamentally alternative method that we also use. We make very substantial efforts to keep things out of the path of vehicles.
It seems to me that these two approaches to making crashes less likely are rather in opposition and I wonder if we have the balance right. For example, if we kept roads unobstructed at all times then drivers wouldn't need to be vigilant.
So how do we balance obstruction against vigilance?
Which is more important?
And is there anything interesting to explore here? I'm honestly not sure.