I changed my route to work because a country lane was relatively narrow.
All drivers would wait behind me on the straight bits if there was oncoming traffic, because there simply wasn't room to overtake. However, every now and then one would go on to overtake on the blind corners, because they couldn't see any oncoming traffic, so it wasn't there (the ostrich approach to overtaking).
I once caught one such, owing to a hold-up just round the bend, and suggested that his overtaking had been cynical with regard to my safety. He said he hadn't thought of it like that. I believe him. I just don't think that our driving teaching system conveys to every driver an understanding of why
Rule 166 and similar advice exists. Therefore, when it's a bike, it doesn't seem relevant to follow it.
Of course, it was a small minority of drivers who had this problem, but in the end a bypass opened and made possible an alternative route that was less demanding of the skills of that minority, so I took it.
Now I just get drivers wanting to overtake on a smallish (but not mini-) roundabout when we are both going left. That's a daft thing to do, but there isn't actually advice against it.
Again, a minority of drivers don't seem to realise that all vehicles straighten out bends, so if you overtake on one you're going to get nearer to the bike (or car) than you thought you would.