As a programmer and a musician, I feel that deliberate practice is much different than the day to day practice of working.
Sitting down and playing scales / etudes / method books every day is very hard, but it's the only way to get better at a quick pace. You can't really pay attention at that level for more than 4 hours (or, rather, I and most other humans can't).
Similarly, I've made concerted efforts to refactor procedural code into functional code, and while that is very difficult conceptually (for me, maybe not you) it felt very much the same way as doing scales.
Deliberate practice is not the same as just doing work, and just doing work doesn't make you better as quickly or in the same ways as deliberately practicing.
Sitting down and playing scales / etudes / method books every day is very hard, but it's the only way to get better at a quick pace. You can't really pay attention at that level for more than 4 hours (or, rather, I and most other humans can't).
Similarly, I've made concerted efforts to refactor procedural code into functional code, and while that is very difficult conceptually (for me, maybe not you) it felt very much the same way as doing scales.
Deliberate practice is not the same as just doing work, and just doing work doesn't make you better as quickly or in the same ways as deliberately practicing.