“Software engineers need long stretches of uninterrupted time to get any meaningful work done.”

I see tweets like this a lot. They sound nice. 4 or 5 hours of uninterrupted time without emails, notifications, or pages is great. But the last few hours are going to be wasted if you don’t take breaks.

Working for very long stretches of time, deep in your head, isn’t all that it’s cracked up to be. I frequently make mistakes when working for, say, 4 hours straight without many bathroom breaks. Worst of all, these mistakes aren’t apparent until the next day after I’ve gotten some rest. I can only imagine that folks whose work demands creativity and problem solving end up in similar situations.

My hypothesis is that my mental zoom lens becomes faulty without rest. Deep focus over a long period of time — say, more than 2 hours — decreases the lens’ ability to zoom out. At this point it becomes easy to stay at whatever level of abstraction I’m operating on or go down rabbit holes. And when this happens it’s impossible to see how any decisions I’m making at lower levels may not be compatible with existing structures at higher levels.

At some point I asked myself “is it possible to train the mind so that zooming out remains easy after focussing for a long time?” This might be incredibly useful, but I’m doubtful that that the work would be worth the results if it’s even possible. The mind automatically zooms out and consolidates information you learned from previous work sessions just as a result of softening focus and resting for a short while. Why forego this natural mechanism?

The exception to all this is if you have everything figured out, you know how everything you’re making is going to fit together with existing stuff, and everything actually connects perfectly like how you thought it would. Unless you’re deeply familiar with existing code and architecture, and have an ounce of luck, it’s unlikely that all your assumptions will be true.

The timeframes used by the subjects of the Ericsson paper — about 60-90 minutes of focused activity with some short or long breaks in between — work best for me. A few sessions of those and I have a solid day with fewer rabit holes and bugs.