[ohyes]

I definitely block out my time for projects and work on one thing at a time for a day or two if I can. Task switching can be expensive, but if you have some state saved outside of your head/computer, it can help jog your mind when you want to come back to the task. So I keep a (paper) journal of things I'm working on.

Coding is all about the mental work, so if you can keep your mind sharp it is good. Get enough sleep and devote some time to learning new things that are beyond (more difficult than) the work that you do. Getting better is all about challenging yourself.