One thing I'm particularly passionate about is clear, expressive code. I believe refactoring is an important skill to learn if you want to get better at writing clear, expressive code. The volume and variety of things I read about refactoring is probably greater than what most programmers read. The amount of practice that I put into doing refactoring exercises is also probably disproportionately greater than what most programmers do.
Just this past weekend, I spent 4 hours practicing with other people online in the latest iteration of Bob Allen's Code Craft Saturday and Sunday (he does this every two weeks so if you're interested in joining, check him out on LinkedIn)
Retrospecting on my experience in those sessions, I had new insights into how I can improve my TDD, refactoring, and
unit testing practice. So even though I didn't find the sessions I joined particularly stimulating or thought provoking, I still did get good value from the experience and the opportunity to observe and think about how other people were doing refactoring in a mobbing situation.
If you're interested in seeing some of the work we did, take a look at this kata:
https://cyber-dojo.org/kata/edit/WGehLz
I didn't think the refactoring results were very good but, well, Cunningham's Law (essentially, post the wrong answer if you want to get the right answer). Now I have a way to see how I could do better.