Pomodoro works in theory but ultimately requires a lot of discipline because it's easy to just ignore the timer. Worse, maintaining half an hour of deep focus just doesn't work for some people, especially the types the article describes. Anyway, pomodoro's only advantage if you want to try to maximize the amount of productivity in a day without mentally bogging you down.

What worked best for me is low-overhead simplicity. A notebook. Make it routine to realistically scope out, jot down, divide and conquer tasks. Just a few minutes every morning. No schedule. Take the task and work. Whenever your brain tells you to take a break, just take a break. But just keep on looking at what you aimed to accomplish for the day. That way, you're just mentally thinking about the tasks and not some stupid timer or how you planned it all out on a calendar.

Ultimately, it's about managing emotions, but having this down helps because it clears your mind a little.

That sort of pomodoro stuff only works on unpleasant tasks that don't require too much thought or creativity

I haven't found that to be true. I have used it successfully at various points to help me stay focused on art projects or other work that I was choosing to do that should have been "fun" but that I was still procrastinating over. The two GUI software applications I've made that I consider "finished" (out of a dozen-plus incomplete) have Pomodoro journal pages in one of my notebooks.