Many of the articles on that wiki is written by people with only rudimentary knowledge of the topic that they're writing about, yet the authors claim to be experts, and "debunk" and criticize things without even doing any research.

Take http://rationalwiki.org/wiki/Scrying as an example.

There have actually been quite a few real scientific studies on scrying, and while there may be little evidence of psychic powers, there is good evidence that staring at a point, for example on a crystal ball or the surface of water, leads some people to see dream-like hallucinations at the point where they are staring. See for example http://books.google.com/books?id=am9NAAAAYAAJ&q=crystal+ball...