From the notebook
I use a practicing note book every day. One of the things I use it for is to write down things that occur to me while I practice that seem like they might be useful. Here are few recent ones.
...feeling tension in my right arm that is unrelated to what I'm trying to play. I can concentrate and release the tension, and it makes no difference to what I'm playing. Where does this pointless tension come from? Habit, I guess.
I'm practicing at a speed that's fast enough to expose things that need work and slow enough that I can figure out how to work on them.
I should play Gershwin songs every day.
The thing I'm practicing is not the notes I'm using.
Another name for 'comfort zone,' or at least a related idea, is 'blind spot.'
Not every exercise is meant to push your playing forward. Some are meant to burn in what you already have.