[nostrademons]

In other articles I've read about deliberate practice, the other elements include:

1. Maintaining a difficulty level that is just barely out of your comfort zone: not so hard that you flail wildly, but not so easy that it's trivial. This is touched upon in the article, but presumably "deliberate" practice also deliberately adjusts the difficulty level in response to performance.

2. Mindfulness while you're practicing. The description of "purposeful" practice in the article mentions seeking out errors and correcting them after the fact. The descriptions of "deliberate" practice I've heard mentioned paying careful attention to your performance while you're practicing, so you can instantly correct or rehearse trouble spots. (And this requires a corresponding attention to the difficulty level so that you can spare this attention to avoiding & fixing mistakes.)