I was once driving a minibusful of archaeologists to Orkney, and in traffic on the A9, in a line of vehicles following a caravan. We were all doing about 50, so not really slow, considering the A9 was single carriageway at that stage, a long straightish stretch, with fairly constant oncoming traffic.
I watched in my mirror as a silver Mondeo type car leapfrogged up the queue, overtaking in the smallest gaps in oncoming traffic, barging back into the line. When he was two cars behind me, I saw him pull out to come past. I could also see the HGV bearing down in the opposite direction. This bloke pulled out, started to over take, realised he wasn't going to make it past us and by the luck of the devil, there was a layby on the other side of the road, which he screeched to a halt in, the HGV passing between us and him in the layby. He was a middle aged chap. Sales rep perhaps.
It was so close that I'd started to work out how to minimise the impact, which way best to swerve and so on. I was convinvced there was going to be a collision, whatever. There must have been a matter of feet between us all.
Anyway, we drove on, with a lot of "Did you seee that, that was close! He won't do that again!" A few miles further on, still doing 50ish behind a couple of lorries and this caravan, I looked in my mirror to see a silver Mondeo type car, leapfrogging up the line of traffic...
I'm sure he thought he was a very good driver, because he hadn't been killed.