Absolutely. A person that is given some liberties regarding how they spend their time at work will usually perform better in the long run than somebody that is forced to “work” for the duration. Granted, this is the case for salaried professionals more so than for menial, minimum wage hourly jobs where the worker is much more replaceable. A professional that you need to put significant resources into to make them an important, contributing member of the organization should be allowed some freedom in this regard. If their job is high-stress, they will just get burned out quicker if the stress isn’t relived in some manner.
