I read "The 150 Healthiest Foods on Earth" (Jonny Bowden) recently and took from it this extremely condensed diet advice: "Avoid grains and industrial processing." Grains have near-zero nutrition, and industrial processing is the source of a lot of questionable practices.
On this diet, which I've followed just a few weeks, I cheat all the time, but I feel and perform better in ways that I can quantify at the gym: more strength, better endurance. Noticeable improvements every time I've gone, so far.
Using the abstractions of loose coupling at early stages of development tends to add more complexity than you gain, violate YAGNI, and give you the wrong things later. Unless you've already developed exactly that kind of software before you'll just make a lot of mistakes.
You have to go through a refactoring process at every stage if you want to achieve a big system with loose coupling.
On this diet, which I've followed just a few weeks, I cheat all the time, but I feel and perform better in ways that I can quantify at the gym: more strength, better endurance. Noticeable improvements every time I've gone, so far.