SOPP617: One measure is just not coming"

This question was sent by David, and he writes, "I didn't see this video when it was posted because I was buried with work at the time. Thank you for posting it and this podcast. This week, I am experiencing the same thing, but with a simple hymn that I should have no trouble with, but one measure is just not coming, and I, too, felt like hitting the (imitation) organ as I was practicing... (but I didn't do it... it already doesn't fully function properly on Sunday mornings). This made me realize that sometimes this is a normal thing to experience."