What bullet chess is good for.

I don't much care for bullet chess because I'm not very fast with my PC laptop. But according to GM Yasser Seirawan, bullet chess can help you see tactics with very limited time. And as we already know, tactical awareness is critical in chess.
​The other bonus is also being ready for time trouble in tournament chess. If you know you can bang out a decent game in 1-2 minutes, you should be able to make the time control.

​Below it's Black to play.

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White focused on e4 and left his Queen pinned. Always consider all threats and break pins before they hurt you.

​1. ...Nxc3 2.Qxc3 Nxe3+! 3.fxe3 Rxc3 +-