datashrimp

I'll see what we can do!

That's good to hear! Blackmar-Diemer is favoured by this ranking system as although it's a longish line, the opponent's move are all fairly probable, with the least probable being Qxd4 at still around 20%.

Great idea!

Absolutely - in the repo, you can adjust for the skill of the opponent https://github.com/davidADSP/chess-trap-scorer.

The analysis so far has been for 1600-1800 players.

The longer lines are technically less probable, like you say - I was trying to capture the notion that a trap is more impressive if on average, moves are likely. How would you define 'sub-optimal' move in your proposal? It's a good idea -would be interesting to see it in action!