I have three ways of doing research on my family history (a) I gather my own research that I can clearly document with primary-source information (NOT family stories), (b) for difficult areas of research (usually in foreign countries), I hire professional researchers who have a good reputation for accurate primary-source research, and (c) I use public resources like geni.com, ancestry.com or other popular subscription web-site - BUT ONLY AS GUIDANCE.  If someone has posted information that would be valuable to my own family tree, I contact the person who posted the information to see if they are willing to share the source where they found that information.  I have found that some Europeans posting to geni.com are actually including a photo of the resource material and a full citation of where that information can be found.  To me, using due diligence in my own research will help assure others of having information that won't send them down blind-alleys or dead-ends in their own family trees.  Blindly accepting someone else's posted research is as effective as doing your family research with information you found on a bathroom wall.