Prisoner's Dilemma strategies
Suspicious TFT (Suspicious Tit For Tat)
Defect on the first move, then copy whatever the opponent did last time.
Played by Warehaven Wanderers Known in the literature as Suspicious Tit For Tat
Where it comes from
Tit For Tat with the opening move inverted. Kept in the standard set because the comparison is the cleanest demonstration in the literature of how much a first move is worth.
How it plays
Suspicious Tit For Tat is the best argument in game theory for the value of being nice, because it is identical to the tournament winner in every respect except one, and it does measurably worse. One move, at the start, against opponents who will remember it.
The damage is not the defection itself, it is what the defection starts. Against another reciprocator, that opening move gets answered, which gets answered, and two strategies that would have co-operated for the whole game instead trade punishments through a match neither of them wanted. The pay-off lost is not one round's worth, it is most of the relationship.
Against a naive opponent the opening move is free profit, and that is the case its supporters make. It is a real case and it is a small one, because the field it beats is exactly the field every other strategy also beats, and the field it damages itself against is the strong half.
On a pitch it is the early statement challenge, followed by a perfectly proportionate afternoon. The tragedy of the strategy is that the proportionate afternoon was available without the challenge, and everyone in the ground can see it except the side that threw it.
In this league
Warehaven Wanderers of Warehaven play Suspicious TFT. That caution is sensible right up to the point where it becomes the provocation. They have not played yet this season.