There is always one...

[PieEater]

I would have just let him pass at the first opportunity and be done with it.

Same here, it's sad that people feel they have to prove themselves through their 'leet driving skillz' but it is best to let them get on with it rather than encourage them to take more risks and put themselves and others in danger.

I get it with car drivers too, I'll come up behind one and start planning the overtake but they'll notice that there's a bike in their mirror and they'll take off trying to prove their car is just as quick as a bike. If I follow enevitably they start taking stupid risks like crossing into the oncomming lane round blind bends so rather than contributing to a potential collision I let them have their 'victory' and catch up to them a couple of minutes later stuck behind another car and then leave them behind.