Why GF without a definitive Diagnosis?

Why are so many people trying the gluten-free diet without a diagnosis? This article is very helpful to explain why the lack of accurate tests still indicate that a diet challenge should be attempted.

What if it works?

http://glutenfreeworks.com/blog/2010/12/28/everyone-on-a-gluten-free-diet-2/#more-2839

This article on celiac com talks about a study showing that non-celiac gluten intolerance is real.

http://www.celiac.com/articles/22430/1/Study-Shows-Gluten-Intolerance-Without-Celiac-Disease/Page1.html

Thread topic:
http://www.celiac.com/gluten-free/topic/77613-study-shows-gluten-intolerance-without-celiac-disease-celiaccom/page__gopid__675314#entry675314