Because they were following so close, they could not see the puddles until they were about to hit them. My road position was a clue, as I moved out to the centre line to avoid them, but that was too subtle for his two brain cells. He managed to swerve around many, a violent swerve each time, with corresponding angry face from his wife, but still did not change his behaviour. But when faced with oncoming traffic, he had nowhere to go but into the puddle. Despite several difficult control issues, he still learnt nothing, stayed at same speed and distance. If I'd been really mean, I could have increased my speed to the limit, still avoiding the puddles, and he would have crashed earlier! I slowed more a few times, where overtakes were possible, and with no puddles on the other side, so also safe for him, but he was incapable of making an overtake. Last option, I suppose would have been to stop and let him pass, but then he would have crashed ahead of me,possibly blocking the road and delaying my journey. So I looked after me.
I doubt any insurance company would pursue me as my statement of events will contain lots of detail about his behaviour, whereas his will contain a few grunts and some abuse!