I disagree with the conjecture. I don’t think to be rational one needs to perform an unusual amount of conscious calculation per unit of time. To be rational, one must simply change one’s default settings in a specific way. This could be done bit by bit over the course of many years.
It certainly takes an unusual sum total of introspection and conscious awareness and whatever to discover just how broken and unreliable our default settings are for the modern environment, but once changed it takes no further conscious intervention to keep those settings in their new position.
For example, it might have taken a long time and a lot of conscious intervention for me to identify and stop eating junk food (or what I consider such), but it certainly no longer takes any conscious thought to reject a piece of candy. I don’t think through everything bad it could do to me or anything and weigh that against how good it would taste; I simply feel a few painful bodily sensations and think, “Ew! Can’t have that!”
So I think this comment by Jonathan_Graehl is spot on. It seems that your conjecture would only apply to people currently making an unusually large amount of changes to their thinking and behavior. Perhaps that’s the case with a lot of people on LW though.
What’s the difference? What exactly do you do and sound like, and what would somebody who it came to naturally do and sound like?