I feel like it's appropriate to bring up meditation, and specifically self-awareness. There's something about seeing yourself as a third party that helps put things into a larger context and helps us "let go".
I think meditation is great, but I am more inclined toward the Western religious traditions that state “faith without works is dead”. Getting outside of yourself by helping others is a much more concrete and visceral experience, with similar results on your mental landscape.
Pomodoro isn't a productivity system. It's "I'm going to focus for ~15 minutes", and that's much easier to do than "spend 8 hours working".
Looking at the article, one example of data collection is "I know that I write at about 20-30 WPM" (the implication being that the author feels pressured to write at a minimum level of "efficiency"). Coupled w/ pomodoro, it essentially becomes a pressure to write X words in Y minutes, lest feelings of inadequacy hit later upon reflection. This to me feels borderline unhealthy: "what if I forgot to measure", "what if I under-deliver", etc are all possible psychological sinkholes.
What meditation promotes is asking yourself what exactly happiness means to you personally, and observing how expectations and accomplishments play a role towards your objectives. Sometimes yes you just need to recognize that you need to get off your ass and do the work, but sometimes it's a matter of prioritization, sometimes less is more.
A task that took three 1-hour sessions is often not doable in one 3-hour session, because you lose creative productivity after a bit of time. That was my first mistake when trying to estimate how long things would take.
Instead, now I calibrate based on time as well as sessions, so I know preparing a new 80-minute lecture (for a class) takes two 5-hour sessions: the first 5-hour session to outline the class and activities, gather the major sources and bullet points I want to make; then the second 5-hour session to put together the polished version of slides and activity script, and do a 60-minute mental run-through.
Same with a lot of other tasks. Some are short but need multiple sessions, like writing recommendation letters that will be closely read. Even though it's easy to write the 2 pages in about 30 minutes, it rarely gets the right tone, and needs at least one or two more 20-minute sessions to capture the applicant's character as clearly as possible.