When I hear developers venting frustrations about productivity and wishing to "bottle up" their flow state, here's what I usually tell them (apologies for the graphic analogy)...
If you have constant "flow", what you actually have is diarrhea, and you're probably just dumping out a bunch of unsustainable crap. You don't want constant flow. You want nice regular bowel movements of code. 💩
You can't force flow. There are techniques to help with it, but you have to be careful to avoid burnout.
Sometimes you just have to go with the ebb and flow (no pun intended). Sometimes stepping away or going for a walk helps. Sometimes doing menial or administrate tasks helps. What works is different for everyone, though I think trying to stick to a rigid schedule is often bad.
