Some people have this problem that they cannot think without words. And writing down their thoughts and decisions is the most effective way to proceed.
So - is it normal and acceptable that I write down my thoughts and decisions in some Notepad++ file during coding?
Sometimes it should be acceptable, e.g. when recreating technical documentation or reasoning about more complex algorithms, but sometimes it may be strange, e.g. when I am considering design options and trying to make judgment.
The impact of this practice on productivity is unclear. From the one side - reasoning with inner words may be faster than with the written words. From the other side - more complex problems requires writing. Besides, if one is stuck with more design options, then the feeling is better when the decision is written, so it rises morale.