Ringer tit-for-tat will always beat tit-for-tat since it will score the same as tit-for-tat except when it goes up against shill tit-for-tat, where it will always get the best possible score.
It will do worse than tit-for-tat against any bot that cooperates with tit-for-tat and defects against ringer tit-for-tat.
But not much worse; against counterexamplebot, ringer tit-for-tat will defect (so almost full double-defect), and tit-for-tat will always cooperate, so for that match ringer tit-for-tat is down about 50 points (assuming 50 rounds so the score is 100-49). Ringer tit-for-tat then picks up 150 points for each match against the 2 ringers, and the score is now (300-349). And it’s only this close because the modified strategy is tit-for-tat rather than something more clever.
Also, this assumes that a bot even can defect specifically against ringer tit-for-tat. Insofar as ringer’s source is secret and the identification is a function of the source of both ringer and shill, this may not be possible. If I understood correctly we only have access to ourselves and our opponent during the match, so we can’t ask if some 3rd bot would always cooperate against our opponent, who would always defect against the 3rd.
It will do worse than tit-for-tat against any bot that cooperates with tit-for-tat and defects against ringer tit-for-tat.
But not much worse; against counterexamplebot, ringer tit-for-tat will defect (so almost full double-defect), and tit-for-tat will always cooperate, so for that match ringer tit-for-tat is down about 50 points (assuming 50 rounds so the score is 100-49). Ringer tit-for-tat then picks up 150 points for each match against the 2 ringers, and the score is now (300-349). And it’s only this close because the modified strategy is tit-for-tat rather than something more clever.
Also, this assumes that a bot even can defect specifically against ringer tit-for-tat. Insofar as ringer’s source is secret and the identification is a function of the source of both ringer and shill, this may not be possible. If I understood correctly we only have access to ourselves and our opponent during the match, so we can’t ask if some 3rd bot would always cooperate against our opponent, who would always defect against the 3rd.
Well, I’d encourage you to submit this strategy and see how it does. :)