Doesn't seem very strange to me. For any (realistic) situation, there are any number of irrelevant false beliefs that you could have while still managing to predict the result correctly. Or even relevant false beliefs that nonetheless produced the right prediction: e.g. a tribe that believed in spirits might believe that sexual intercourse attracted a disembodied spirit into a woman's body and caused it to grow a new body for itself, which would be false but still lead to the correct prediction of (intercourse -> pregnancy).