The school principal insisted that student failures are caused by bad teaching. In a relatively short time failing grades disappeared from the school. The principal happily recognized this as evidence that the teaching had improved at the school.
The flawed pattern of reasoning in the above is most similar to that in which the nutritionist insisted that the weight gain that team members complained of was caused by their thinking of food too often. The nutritionist was happy to conclude that the weight gain had stopped once the team members reported that they had stopped thinking of food so often.