[Almaviva]

The argument that "the brain knows better" seems very weak. The brain also wants people to over consume fast food, reward itself with alcohol and drugs, and several other things which obviously aren't rewarding in the context of modern society.

[squasher]

Right, I second that. Also, I used to "take breaks" by playing games or putzing around on the internet, until I realized that it doesn't actually help me feel relaxed and energized. But stretching, walking around, getting a cup of tea, and most other things in meatspace get me ready to go back to work.