I stopped using pomodoros for flow-work, because it would break my flow state. I've found roughly 2 hour chunks work better for flow, without any particular warning to stop me if I feel like going longer. If I am in flow, I want it to keep going as long as possible, until I am fatigued, or the problem is solved.
I'm not sure if you've read Mihály Csíkszentmihályi or not, but he argued that flow states are more likely when a task is more complex/challenging, and the person has a high level of appropriate skill that makes it possible (with substantial effort) to complete the task.
For me this often occurs while programming, sailing, or doing math- especially if I need to solve a new problem with those skills that will be especially challenging.
Once I'm in 'flow' it is a distinct mental experience - I am totally into it and lose any sense of time passing, or of needing to motivate myself until I am interrupted either by my own body, or by something external.
Cal Newport in Deep Work (his own word for flow work) defines "Deep Work" as anything that requires skills that would take at least a year to develop if a person was already generally educated, smart, and motivated.
Cal Newport in Deep Work (his own word for flow work)
I'm not sure that's an accurate description for Cal Newport's Deep Work. High intensity deliberate practice that you can only do for short amounts of time per session is Deep Work in Newport's model.
CGP Grey follows a cycle that repeats -> (40 min work - 7 min break - 40 min work - 20 min break). I think he mentions it in here somewhere but I don't know the exact time. It seems probable that the most appropriate length and cycle for an individual should be based on their attention span and recovery.
I used to view pomodoro timers as good for production type work but not for creative, in the zone work. This model served me well. There have been a few surprises. I had assumed that studying was creative work and therefore would not benefit from a timer. Barbara Oakley's Coursera course "Learning how to Learn" recommends the use of a pomodoro for studying. Both the coursera course and her book "A Mind For Numbers" goes into why this is the case.
I much prefer to use pomodoros in continuous mode (auto renew after 5 min break).
When I use a computer, I find it useful to have my screen automatically block for 5 minutes after every 30 minutes, and I use some cognitive tricks to feel grateful instead of annoyed when it happens.
Here's a Linux system tray pomodoro script that I made: https://github.com/guciek/linuxutils/blob/master/genmon-pomodoro
After our recent LW Dojo in Berlin we had a conversation on our mailing list about pomodoros.
How do we handle it if the bell rings but we are in flow? Is it good to honor the bell and take a pause or is it more effective to continue working to keep in flow?
The original setting of 25 minutes came from the 25 minutes that Francesco Cirillo tomato shaped timer had naturally. The LW Study Hall seems to use 32 minutes work with 8 minutes pause. If you have experimented with different lengths, what worked for you?
Did you come to any surprising conclusions about pomodoros while working with them, that might be interesting to other people?