That's not an effect. As both in the case of a dividedend and a stock buy back, the company's market cap drops by the amount of cash that's being distributed out, creating an identical re-buying situation in market cap-weighted index funds. Stock price itself is irrelevant for index fund rebalances (unlike for shareholder returns).
It's not documented, but unfortunately neither of these re-signs the commits even if GPG signing is configured. They are based on `git replay`, and that doesn't sign either (at least yet).
I don't have a concrete example, but I think you can invent plenty of iterated prisoner's dilemmas with whatever modified rules and variables and find 'tit-for-tat' isn't the end-all-be-all. Like it changes things if there's an infinite or an unknown number of rounds, some of the defects are 'noise', etc.,.