We're 0% productive most of the time. Sleeping, commuting, meetings, lunch. Adding a negligible amount more for tooling is not really an issue.

I'm essentially dependent on Eclipse when doing Java. It takes me Back when I was on a Civil Engineering path, an elderly engineer said "I bet you don't even know how to use a slide rule, what do you do when the power goes out", to which I responded, "I go home, same as you, unless you've got candles in your desk too, and let's not even get into air conditioning".