> Do people actually think in terms of complete sentences like you describe in this passage, or is there some nuance to the experience I’m not understanding?

I do full sentences when I’m thinking about how to handle a conversation.

> Thinking for me feels more like watching thoughts flow between black boxes representing some known factor than talking to a friend.

I also do that. It’s situational, I guess. [I’m learning more about myself by questions like yours, so please keep asking :)]