I want to point out that Eliezer's (and LW's general) use of the word 'rationality' is entirely different from the use of the word in the game theory literature

And the common usage of 'rational' on lesswrong should be different to what is used in a significant proportion of game theory literature. Said literature gives advice, reasoning and conclusions that is epistemically, instrumentally and normatively bad. According to the basic principles of the site it is in fact stupid and not-rational to defect against a clone of yourself in a true Prisoner's Dilemma. A kind of stupidity that is not too much different to being 'rational' like Spock.

ETA: Reading Grognor's reply to the parent, it seems that much of the negative affect is due to inconsistent use of the word 'rational(ity)' on LW. Maybe it's time to try yet again to taboo LW's 'rationality' to avoid the namespace collision with academic literature.

No. The themes of epistemic and instrumental rationality are the foundational premise of the site. It is right there in the tagline on the top of the page. I oppose all attempts to replace instrumental rationality with something that involves doing stupid things.

I do endorse avoiding excessive use of the word.