While Zen does enable positive results to those who practice it, I believe its claim of 'enlightenment' is dubious with a need for a lot of reservations.
Here is a popular article re Soto Zen and its dark side, i.e. its Zen ideology which enable its leaders to be embroiled in sexual scandals and other abuses.
This is about Richard H Baker who inherited the Zen leader of the Soto Sect from Shunryu Suzuki of the San Francisco Zen Center.http://www.thezensite.com/ZenEssays/Cri ... e_Myth.htm
Most people think of Zen as being iconoclastic, anti-authoritarian, simple, direct, and unattached. Its raison d'etre is to produce people who possess a fundamental insight into life, people who are not fooled by appearances or ideas.
The fact is that almost everything about Zen's presentation, practice, and rituals is aimed at producing people who give up their good sense with the promise of a greater gain in the future. While this is obviously a general statement that demands further qualification, it serves to introduce some of the basic problems to be dealt with here.
This article also point out how the whole set up of Japanese Zen started [adapted from Chan of China] and from the beginning it was never holistic thus enabling all sorts of scandals not confined to Soto Zen but also other schools of Japanese Zen.Michael Downing's book, Shoes Outside the Door: Desire, Devotion, and Excess at San Francisco Zen Center (2001) describes much of the sexual scandal surrounding Richard Baker, as well as financial problems and Baker's generally arrogant behavior.
My point is,
while Zen do provide some positive benefits but it is not holistic especially if one cling to it based on faith without the necessary critical thinking.
But the catch-22 with Japanese Zen is that it does not permit nor condone 'necessary critical thinking' just like those of the Abrahamic religions and other dogmatic faiths.
The article is worth reading for knowledge sake or for anyone thinking of getting into Zen.