Do not make abstraction - hell, yes

I totally agree. My earlier and super messy bot, which I could not understand today, had significantly more brain and overall sense of the battlefield. It was somewhat easier to hack too (when I was able to keep it in my head).

Downside, I cannot understand it now. It was easier to write a new one that perfect the old one.

But I notice that modular approach goes same route, too many modules which I cannot keep in the head to understand fully.

Whether to go modular or not, this is a dilemma. However, in principle, the less code it has, the easier it is able to fit in brain. So after many years struggling with modularized design, I decided to start from scratch and keep it simple.

Modularized design does come with good part — you don’t need to fully understand the code before you start to hack it. ScalarR’s code is written many years ago and I’m still able to hack some modules, even if how the rest part works have been forgotten. But making big changes is very, very hard because the code has been spread out into many, many submodules.

The point is, making big changes is better than small tweaks. So instead of rewriting so many modules, a compact and yet often rewritten design is supposed to work better. You get punished for writing to much logic in a compact design, so more machine learning and less tweaking ;)