This is answer 1C in "BizQuiz: Working with overeager horse owners."
1C. Really wrong. Telling clients where to stick all that half-baked Internet research can be satisfying, but it doesn't serve you, the clients, or the horses.
The clients who share what they know often bring Internet research and reading material. Don't discount their opinion or sources of information. Instead, look at the materials, and acknowledge their efforts.
These clients usually mean well; they're not trying to undermine your authority or toot their own Internet-search-savvy horn. So while you may feel that they don't trust you, they're just thinking about their animal and its care. They're looking for the best answers.