You are right, in that accidents can happen anywhere regardless of the cycling activity being undertaken. But my personal view is why hold a cycling event on such a busy road. I believe there was a death on the A1 not to long ago while time trialing, again its a personal opinion but I wouldnt dream of cycling on the A1 and I regard myself as an extremely competent cyclist.
There are a couple of TTs near me wish are on very quiet roads, where hopefully the chances of an accident are greatly reduced.
I think they are held on more main roads because they tend to be longer, straighter and flatter with less twists and turns, so allowing the ride to be fast.
i know this area. Apparently Cath was at least half mile past the roundabout, not just coming off it. Friends have told me the driver had clear visibility. Also almost no traffic around at the time of the accident, meaning he could have given her a wide berth. Respectfully, i don't agree with your view about holding time trials on busy roads. I think that having more cyclists on the road actually increases drivers awareness of them as they see them one minute apart and should have the brains to work out there is an event happening.... or perhaps they are just not paying attention. Mmmm.