Ah - tactically a tough spot. You're not going to out-point a mono after the rounding in that situation, and I see that tacking away wasn't an option. I imagine I would have footed hard to try and break through his lee - if there's a good bit of track left, you really need to get by him to make your rating work. If you're near the finish, you might not have any other option than to do what you did - lock in and hold with him as high as you can to keep ahead of the Pac Men behind you.

Sportsmanship? Supposed to be at the top of the pile throughout the course. He was being a sportsman, in a way, by using the tactical advantage to cancel out your speed advantage. That's a good opportunity for discussion at the bar later - "Hey, good job holding me off after that last mark. You know I would have gotten you if I broke free, right? Cheers - I'll get you next time."