I know it sounds batshit crazy. I know it's not science. I know I'll be moderated to "shutup dumbass". I'll say it anyway.
I grew up in rural Oregon. My family moved there in the early 70's, from California. We bought a big chunk of land, with nothing but trees on it. We pitched two tents, and started searching for the best house site. We filled 5 gallon bottles at the neighbors for a while, until we decided where to build the house.
The neighbor's father was a well witcher. We assumed that it was part of a big joke on the city slickers, but humored him, and let him witch the well. He had a forked stick, and walked around for 30 minutes with it. He said "drill here. at 60 feet, you'll get 10gpm, but keep going to 80. At 80, you'll get 20gpm". We offered him money, and he said this was a gift from God, and he refused any sort of payment.
When the drilling rig showed up, they asked where we wanted to drill. Keep in mind that there are no maps, no charts, *nothing* to tell you where to dig. The guy with the truck will always suggest a spot; the one with the easiest access for his giant truck. So we drilled where the old man suggested. The driller shrugged his shoulders when we told him to keep drilling when he hit good water at 60 feet; he gets paid by the foot, regardless of water output. We got 20gpm at 80 feet (I don't remember the exact numbers, but it was within a foot or tow, and a gallon or two).
20 years later, my folks built another house on the property. They got the well witched again. It was a different guy, but a very similar story. "Gift from God, no payment". Accurate prediction of depth and volume of water.
If I didn't see it myself, I'd call bullshit.
That said, I'm sure there's a million scammers out the now.