to bang my head against. Or more to the point, someone else's head.
I took an IAM Associate out on Sunday and I told him, when you stop on the road (e.g. at traffic lights) or before turning into a different road, you must do a lifesaver before moving off. He did it at the next set of lights, but failed to do it thereafter.
I pulled him over in a convenient car park and explained it to him again. He said "OK, yeah, I understand". He then set off and didn't do the damn lifesaver. I let that one go and carried on observing him. 10 mins later, I pulled him up again and said "You know the lifesavers we spoke about? Well you're still not doing them". He said "Oh, sorry" and then set off again, without doing the bloody lifesaver. Grrrrrrr.
He's been riding for decades and can't manage a simple thing like that. He's got his test next week. If he passes, I'll be gobsmacked.