Another piece of evidence is this minor error in section 9.2 of Peterson’s An Introduction to Decision Theory:
According to causal decision theory, the probability that you have the gene given that you read Section 9.2 is equal to the probability that you have the gene given that you stop at Section 9.1. (That is, the probability is independent of your decision to read this section.) Hence, it would be a mistake to think that your chances of leading a normal life would have been any higher had you stopped reading at Section 9.1.
Another piece of evidence is this minor error in section 9.2 of Peterson’s An Introduction to Decision Theory: