I watched some primary school tournaments and tournaments for high schools in Germany. I noticed that some kids (around 10) have several (3 or more)games unter 20 in the analysis. They all have no ELO or are under 1200. I though that under 20 in the analysis is around GM level? What exactly does it mean to have several games under 20 even though you have a low rating? I don't want to accuse anyone of cheating, I am just curious how that can happen.
I assume you mean under 20 acpl. Simply I believe anyone can play an almost perfect game every once in a while, though it becomes suspicious when these results happen very consistently.
Please user lichess.org/report if you find suspicious behavior or gameplay.
It may be cheating, but another explanation is: If one player blunders very early, the other one can easily achieve a low acpl, because his faults are no longer counted as long as he keeps a winning position.
If you know openings well and the traps inside them then every now and again someone will fall into a trap and you can beat them early in the game. This will mean you technically played a perfect game although you didnt actually play many moves.
It's *average* centipawn loss. Meaning when someone is dragging out a lost position, then the opponent will be better for many moves, lowering the average. That number doesn't say much.
More important is how many mistakes someone made, and that you have to see move by move, because the counter in the analysis doesn't include mistakes after which you are still winning, except when you missed a forced mate.
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