That was my first reaction as well, until I noticed this phrase in the post which made me think:

I had read all the sequences before, but I have found that since I've started using the cards I've noticed the concepts coming up in my life more often

Likewise, I've read all the sequences many times over, but the skills described there just don't come up othen in real life. Sure, it might be because they aren't very useful. But also it might be because I compartmentalized them and keep forgetting to apply them when opportunities arise. It might be worthwhile to try out spaced repetition to test that hypothesis.

On the other hand, Schelling's ideas stuck with me after reading the book once and I immediately started applying them, seeing conflicts and precommitment moves everywhere. So maybe Eliezer's findings really are useless for mortals :-)