I think any credible experiment must relate to the original phenomena in question. Can people use dowsing rods to accurately detect buried lines or objects?. From my research most prior studies were inaccurate, biased and outside the context of what was actually being studied. Most past experiments were set up to look for a nonsensical "psychic phenomena" not a subconscious reaction (ideomotor effect) to the surrounding environment. In effect, they designed the experiments to fail by introducing unnecessary elements they knew would probably fail which is clearly biased. For example, it's well know hunter/trackers can track animals for miles from the smallest environmental details 99% of other people are completely oblivious to. Should we deem the tracker a psychic and test there physic abilities?. Maybe we could put the animals in closed containers and then have the tracker guess which one contains an animal. It sounds completely absurd yet this is exactly what many supposed dowsing studies did in the past. In any credible dowsing experiment were trying to measure the dowsing wire motion relative to the position of known/unknown buried targets. Who the dowser is, there opinions or beliefs have nothing to do with it. Most people like to confuse an issue with there own biases which is why they need to be removed from the equation. Were simply measuring the dowsing wire motion relative to a target then correlating the data to determine how accurate the process is.