Here’s a challenge for you — the kind of task you’d have to solve on an Elo project job interview. I’m recording it here so that I know where to find it in the future. At Grand Prix Chiba last weekend two different people with the name Ryo Takahashi registered for the event. Both of them went 6-2 on Saturday and advanced to day two, when someone realized that there were two people with the same name. In Sunday’s rounds the two players have the last four digits of their DCI numbers attached to the end of their names so that they can be told apart. But if you look at, say, the round 4 results, you’ll see two people with the same name. Using the tiebreakers of the two players (and some of their opponents) you can figure out whose day one results are whose. See if you can accomplish this. The correct answers are here on the site if you want to check your work, and of course I’d be happy to provide explanation if you want to know how to do this. It took me about twenty minutes to disentangle the two players’ results, and my guess is that if you have never tried to do anything like this with tiebreakers before that you’re going to need to set aside at least an hour to figure it out.