I do think that it is important to take time “off” from school work. But how you do that needs to be personal to you. Many teachers I know go in fits and starts, where they participate heavily in the social networking related to school outside of school hours. Then they can go for periods of time where the school stuff stays at school.
The article had some very good points to it and is something worth sharing with teachers who might be stressing about their balance. Another thing that I have found is that the more experience I get, the less stress I have about getting school work done. I know that I will get it done and I know that I will have to give up something (maybe a small something, like having a relaxing non working lunch, ha ha!) along the way to get it done. I have come to understand and accept that, instead of worry and stress about it. I am sure this attitude is true with many jobs and experience.
I think that you just have to find your balance. Mine comes from horses. Spending time near them keeps me sane! Find the thing that allows you to have balance and do it whenever you can.