As other commenters have mentioned, I’ve noticed that people generally tend to fall into one of two groups: those who think out loud and those who process internally. (And I don’t know if it’s a coincidence or not, but almost all of the managers I have had in my career have been the former.)

I tend to think internally, and while I usually have a clear vision in my head of how a system works, if I try to translate that mental model on-the-fly into an explanation for others, it typically comes out as an incoherent jumble of loosely related phrases.

To that extent, I much prefer written communication. It gives me time to convert the thoughts in my head into English, and I typically iterate on what I’ve written down quite a few times until I’m satisfied with it (including Hacker News comments for example).

The one exception to being a “slow thinker” is if the discussion involves a topic I know very well and someone says something that is incorrect or inconsistent. While I can’t necessarily articulate my own ideas immediately on the spot, I do seem to be able to quickly identify and explain flaws in deductive reasoning or come up with examples that highlight inconsistencies.

I’m not sure I necessarily like that my brain defaults to looking for flaws in arguments rather than reasons to support them, but my own internal process of generating ideas consists of a cycle of proposing an idea to myself followed by immediately trying to find ways to shoot it down (such that whatever ideas survive this mental gauntlet are decent ones I guess). But I think this approach had the unfortunate side effect of optimizing the “quick thinking” part of my brain into that of an inconsistency-detector rather than a rapid brainstorming mechanism.