This reads like: "What we thought was a slowing down of mental processes was probably actually just thoughtfulness and the avoidance of jumping to conclusions early."
This reminds me of how people believe (i only have anecdotal evidence, but LOTS of it) that reacting faster in conversations means you're more intelligent, when in fact the opposite must be true.
The brain can super easily pattern match in conversations and will, in absolutely most cases , spit something out that fits to the patterns of the words spoken (as evidenced by speaking with people who react quickly, regardless of how stupid the reaction is), but that doesn't make intelligent.
It makes thoughtless.
Even worse than those are the ones who seem incapable of reflecting on their thoughts, insisting that they are correct, actually refusing to put a second or deeper thought on it.
Those are mindless automatons.