I am not dismissing it. As James R has said, it is easy to prove. Bury several pipes, some with water, some without. If the dowser can detect which pipes contain water, then there is objective proof of their ability. No such test has resulted in a confirmation of their ability. And again, if the person says "well, I can't do that! I look at property and look for drainage, soil type, slope etc rather than detect pipes" then great, they are good hydrologic engineers. They are not dowsers.