Coming to a controlled stop and keeping control of the situation before the road opens up can be preferable when you have someone behaving unpredictably. I've been in a similar situation where I have pulled to the left only to find that the idiot behind is attempting to undertake. I've also been seriously injured by a tailgating motorist as I've pulled left out of their way, I wish that had happened at a slower speed.
And also Vine didn't slam on the brakes.
Coming to a controlled stop and keeping control of the situation before the road opens up can be preferable when you have someone behaving unpredictably. I've been in a similar situation where I have pulled to the left only to find that the idiot behind is attempting to undertake. I've also been seriously injured by a tailgating motorist as I've pulled left out of their way, I wish that had happened at a slower speed.