Seeing this where he's asked if anyone could have interferred with it and saying he's not the most observant person in the world reminded me of a tale from a friend of mine years ago. The story is from the time when a ford cortina banger was possible to buy for from £5 to £50 and his was roughly middle of this range. He was sat in static traffic due to a combination of roadworks and an accident leaving no-one able to move. A half car gap appeared in front of him so he goes to edge forward, engine revs, could feel transmission working and hear movement at the back but wasn't moving forwards. Got out to find someone had stolen the back wheel on the side of his car without a wing mirror. If that wasn't infuriating enough. The driver behind him starts sounding his horn for him to move. During the time someone had jacked up his car, put bricks under it and taken his wheel, they and all around have done nothing to alert him. Now he is an obstruction they are able to give him grief. Literally none of us believed him at first especially because he was on a section of road literally passing one of the main police stations in the area. But one of the delightful people who had stayed quiet during the whole thing wrote into the local paper about it and they ran the story as a demonstration of how little use the local police were being. Of course no mention of how useless they were all being by just sitting there watching it happen.
Happened to me the same. For years have seen mamy versions, look for it again, and still makes me laugh. This guy is pure technique: in this specific version he was tired, you can notice. Evem though it's not his best, he did a great effort.