The Yated a few weeks ago had an unfortunate vignette with Rav Ruderman ZT”L. Every Friday he would have a line of women asking him chicken shailos. One woman kept showing him good chickens, and he would declare them kosher. One week he finally asked her, “The chickens you show me have no shailos on them. Why do you bring them in?” She answered, “Someone told me A&P chickens aren’t kosher. I feel better serving them after you tell me they’re kosher”.
A rabbinical answer is only as good as his knowledge of the real question.