The concept of mines is easy to understand, you just guess the boxes that you think do not contain a bomb because when you happen to choose the one with the bomb, the round match is over. The only really difficult thing is to win because the only thing you can do in this game is a guess, there are no hints that will help you to have a chance to avoid those who should not be chosen.
I guess there are always algorithms are used for mines and any games. I played mines on Windows and get bad results and I can not get the math behind it. My uncle plays the game very good and I have never asked him how he can play like that. If what you said is only guess, I don't think he can always guess better than me.
Maybe he gets some ideas on the math of Mines game and applies it to play better. Luck is beside him, maybe but he does know the secret of the game.