The Teddy Bear Effect is more powerful than what most people think. Has
worked for me many times.

The Teddy Bear Effect refers to the phenomenon where a passive
listener appears to impart wisdom to a speaker without doing anything
other than listening. People who ask someone a question expecting to
learn something from the answer often discover the answer for
themselves simply through the act of phrasing the question verbally.
The listener is compared to a Teddy Bear because evidently a stuffed
animal would have served the same purpose.

In medicine, the Teddy Bear Effect is sometimes compared to the
Placebo Effect.

http://en.wikipedia.org/wiki/Teddy_Bear_Effect