Comment by dllthomas

> The game "tit for tat" requires you actually tit if you get a tat.

My understanding is that in iterated prisoner's dilemma, "tit for two tats" will often outperform "tit for tat", so in its original setting that's not really the case.

Here in reality, of course, "tit for two tats" can be better exploited if it can be (easily enough) identified and there are more potential ways of doing that.