The amount of effort I do to try and avoid using double parentesis is trully herculean.

I think that stuff is the product of a completionist/perfectionist mindset - as one is writting, important details/context related to the main train of thought pop-up in one's mind and as one is writting those, important details/context related to the other details/context pop-up in one's mind (and the tendency is to keep going down the rabbit hole of details/context on details/context).

You get this very noticeably with people who during a conversation go out on a tangent and often even end up losing the train of thought of the main conversation (a tendecy I definitelly have) since one doesn't get a chance to go back and re-read, reorganise and correct during a spoken conversation.

Personally I don't think it's an actual quality (sorry to all upvoters) as it indicates a disorganised mind. It is however the kind of thing one overcomes with experience and I bet Mr Torvalds himself is mostly beyond it by now.