When teaching elementary checkmates to children, I often suggest they should know the basic techniques so well that they can perform them without thought with mere seconds left on the clock. Sometimes I mention an extreme example. Ryan Ackerman and I spent some time at the Spokane Chess Club one evening taking turns checkmating with queen and king against lone king. Ryan set his Chronos clock so that we each had ten seconds. We were each able to execute the checkmate in six to seven seconds with some consistency, although there was more than one stalemate through the course of the evening. Once, I played the nine or ten moves to checkmate in five seconds.
2017 CARIFTA Championships (Kingston, Jamaica)
9 hours ago