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This is true. Also VGC exists, but it was for emphasis.
I might be misinterpreting you, but it sounds like you can accomplish this exact goal by not clicking "cancel" when you're at 10 seconds of time or under.
Wouldn't that defeat the purpose of the cancel button? If you go to override your move, what happens if the opponent clicks before you choose another action? You're stuck with the move you wanted to cancel.
I don't understand how this prevents timer losses. How long does it take you to cancel a...