Note: I'm typing this without looking at other comments because I judge that it would be really easy for one of the better-sounding argumants to hijack my train of thought, leaving my previous thoughts to be crushed under the wheels of the huge locomotive.

I'm going to do my own 'black box' treatment of rationality, trying to figure out what I've actually got from it in list form.

1. I have a model of the world which allows me to suffer less emotional harm when other people are upset that I (to paraphrase) don't share their preference and/or utility function.

Truth Finding?: I note that this benefit is actually independant of whether rationality is an effective method of finding truth.

1. I have something to protect, and emotionally benefit from this.

Truth Finding?: See 'Truth Finding?' notes above.

1. I found out about using Spaced Repetition.

Truth Finding?: I haven't used it long enough to experience significant benefit from it yet. I also note that I started using Anki mostly because a bunch of people that I considered smart said it worked and recommended it.

Interesting. I'm going to hold off on proposing solutions, think a bit more, and look at other comments.

EDIT: Odd. I listed my items as 1, 2, and 3, but they all show as '1'