Are we really going to point at a choice of route for the cause of this? If it was really that unsafe then like many A roads across the country it would prohibit cyclists, especially with it being the main route out of Lands End. There must be hundreds of cyclists every week using it throughout the summer.
I'd rather be within the hard shoulder and highly visible on a wide duel lane road with plenty of space to be overtaken, than confronted by a boy-racer on the wrong side of the road on a blind corner of a country lane.
There's also a difference between a road being safe for cycling on and a cyclist being safe/experienced enough to cycle on a busy road of that kind. As I said earlier too, a cyclist or a motorist could have a lapse of concentration at any time on any road that could lead to an accident of this nature.
We don't know whether the motorist or the cyclist was at fault and whether the circumstances were unique to the fact that both were on this particular road or not.
I'm all for a thread to express sympathy on these occasions, but do wish they wouldn't degenerate into often wild and moral speculation of the causes before they are known.