Archaeologists can be considered a specialized form of anthropologist,
classicist, historian etc. depending on their field of study.  They should
consult with others in their own field (anthropology, classics, history) as
well as other archaeologist, and other social scientists.  These related
disciplines are interrelated and have a wide literature that not everybody
could possibly be a master of.  By reaching out to others in the social
sciences we can 1. keep from reinventing the wheel 2. gain access to vital
information that we might have missed.  When I stated that a good historical
archaeologist has to be in part a historian (which means gaining some formal
training and reading the work of historians), I did not mean to suggest that
somehow non-archaeological historians were irrelevant  or that archaeologists
could not benefit by consulting them in their research.  I just was shocked
that a historian would not recognize that historical archaeologsts are more
than just antquarians,but represent in their own right a subfield of history.
 Historical archaeologists frequently have degrees in history and gain
appointments in history departments.  I am not a historical archaeologist,
but am an archaeologist with formal training in anthropology.  I have taken
courses across the field of the social sciences, and do reading outside of
anthropology (including history)  so as to gain a sense of what these other
disciplines have to offer, this helps in fashioning appropriate questions to
historians, economists, sociologists, art historians, and geographers.  I was
simply reacting to the "who do these archaeologists think they are" blanket
chauvanism.
      A point in one postings expressed the opinion that it is dangerous to
rely on the English translations of colonial spanish sources.  This is quite
true, and while it would be helpful to become conversant with Colonial
Spanish and haliography, until one has the time to do so, and even after one
has done so-it never hurts to consult someone who specializes in the field of
such documents.  After all they probably have a greater mastery of the skills
and already have a familiarity with documents that may have been of interest
to you.  The same is true if the documents are in Medieval Latin, Ancient
Greek,  Old Norse, Akkadian, Nahuatl, or Chinese.
      So its much better for various social scientists to be allies rather
than enemies.