Very true. History, like science and other fields of study, are always open to revision based on new evidence. It _can_ be subject to fads, like any other group human endeavor, but overall, historians do try very hard to provide evidence for the stories they tell. Archeology was probably one of the best things that happened for history, and the more and more knowledge we gather about etymology and language change in general, we get better translations and better understandings of historical writings in proper context. The stories told by historians continually improve overall.