I play on chess.com and I noticed that at some times I am getting beaten by 1700 pretty easily but other times I can beat 1900 with almost no effort. I broke my record and passed 2000 in bullet recently, now I am fighting with 2000 and 2100+ bullet players. Also, I nearly broke 1900 in blitz.Can I say my game has improved? I recently started to do tactics on chess.com, and it might have to do something with it.
But the problem is when I play my brother OTB, I am slightly better, but he is 1300 blitz rated on chess.com. What is going on with my game?