When my students have a spot that they just can't play without a mistake, I sometimes get to the end of my rope and draw pencil "bars" around the bars. Two students in a row ended up in jail, go directly to jail, do not pass go, do not collect $200.00.
First we do Left Hand 3 times IN A ROW correctly. Then we do Right Hand 3 times IN A Row correctly. I keep count on my fingers and call out the number correctly that they have done. If they make a mistake, I make the game show buzzer sound, dun dun DUHN, and they have to try it again. This works even better when you can really laugh it up. "Oh NOOOOOOO, you whiffed the third one!" Start again at zero.
When we finally get each hand alone, "we" have to get it hands together. This took a whole lesson for a young lady. 30 minutes - four measures. We had 4 other books I was hoping to get through. Heavy sigh.
But this wasn't about those 4 measures really, was it? This is about perseverance, diligence, and learning how to practice something. The details are what matters. Perhaps sometime she will transfer this grueling task to something else in her life, until she gets it just right.
"What? The lesson is over already?" she said. I said, "Yes, and you are now in jail every time you play this piece this week. You must start in jail, right here at measure 12-16, and play it three times IN A ROW correctly before you start at the beginning, just like we did here."
*Groan* "I want a 'Get Out of Jail Free' card," she said.
Don't we all, sweetie, don't we all?