I like the days-of-the-week analogy, but in this case he adds a fifth beat to a bar, so it's like he's adding a fifth day to an otherwise four-day week, as foll

I like the days-of-the-week analogy, but in this case he adds a fifth beat to a bar, so it's like he's adding a fifth day to an otherwise four-day week, as follows: 1 2 3 4 1 2 3 4 5 1 2 3 4 1 2 3 4 C - C - C - C - C - C - C - C - C …so the claps (C) move from the 1 and 3 to the 2 and 4. That fifth beat occurs at the 40-second mark, and can be spotted because he stops playing with the left hand and the right hand simply repeats what it played in the previous beat.