Idiot driver gets slowed down

I was driving home from work earlier today. I'm based in the UK, so those are the driving rules and conditions that apply.

I moved to the right at a large roundabout. This particular roundabout is just off a motorway. I was intending to exit at the motorway exit, which has two off ramps. I moved into the right lane to make sure I'd be ahead of the lorry that I was currently stuck behind.

I hit traffic lights still on the roundabout. Then I saw a sports car behind me, who moved into the left hand lane, now in front of the lorry, which was moving slower due to the nature of the road. He then proceeded to cut in front of me. This was entirely unnecessary. He did take the same exit as me, but wanted to make sure he beat me to it.

Basically he was moving between lanes as many times as he could, just to stay ahead of everybody else. Typical sports car driver. He was older, which I'd glimpsed as he passed me.

That really annoys me, when people do this sort of thing unnecessarily. So as I moved onto the motorway, i moved as far to the right as possible, as soon as possible. I made it into the fastest lane, while the sports car was still in the middle lane. I then sped up and caught up to the cars already in that lane. This worked easily because of it being a Sunday, and about 9am (I'd worked very early). He was waiting for space to move into the fast lane.

I managed to get in front of him through this luck of timing of the cars. He pulled in behind me. At which point my pettiness was allowed to play out. I maintained speed until I reached cars in the middle lane. Then I slowed down and matched their speed. He started flashing his lights to get me to let him pass. I ignored it. I could see him waving his hands and getting frustrated. I kept doing it.

After 10 minutes or so he did manage to find a gap to undertake me. I tried to speed up to not let him pass, but I knew he could leave me in the dust if he had the room, which he did.

As he passed me I just turned and gave him such a massive grin. It was the best I could do to wind him up that little bit more.

And I should add that I have front and back cameras, so wasn't overly concerned about road rage. They're visible and act as a decent deterrent.