I completely agree yet this is sort of at odds with the “flow” based productivity which I rely a lot on — but then again if you are flowing maybe it also means your body is feeling at its best and doesn’t need a break in that moment? Would be interesting to look for some studies documenting this approach. I do have the Flow book but haven’t gotten around to it yet, but I hope it mentions breaks and how they fit in that process. It’s the only way for me to feel productive with certain types of activities!