1. I do something similar quite frequently in informal contexts, and have to catch myself before posting such text to more formal settings. If Satoshi was as aware of stylometry as the article claims, it stands to reason that he would edit those out of his writing. The article is clear that Satoshi’s writing is generally more concise than Beck’s, which may have been highly intentional; parenthetical sentences are generally the opposite of concise (they’re often used to go on a tangent or ramble, etc.).

2. Similar to 1 - a quirk that is easily caught by editing, if your goal is to sound more refined and precise. Academics know it’s i.e/e.g but the dots may get omitted when writing quickly.

3. Interesting observation. That’s a fairly stark difference! Are there other posters who do not use “nor”? If Satoshi doesn’t use “nor”, does he use a grammatically incorrect alternative, or are his sentences just structured to avoid it?