It just looks to me
like he's only blocking when it's not particularly safe to overtake (crossroad ahead, thin road & cars coming the other way), and comes a cropper when he moves in and signals that he car can overtake because there are no cars coming the other way.
The big swerve to the right is just before signalling - he's checking it is clear to overtake.
(
monkeon schmonkeon, Thu 22 Dec 2022, 12:56,
Reply)