Dear Joe,
RC sources are not being treated any differently than others - like all
sources they are assessed for their historical accuracy, truth, and
wieghted one way or another on evidence of biased perspective. As you so
rightly say any eveidence from the 'official' record is written by the
victors and must be wighted in the same way in the light of that source's
consistency.
For example, accounts of the Wat yler Rebellion are weihted for bias as they
are written by the class which was under attack by that rebellion.
SS/Gestapo statements about Jewish life are similarly evaluated and RC
sources on those it judged 'heretics' given exactly the same treatment. The
only other alternative is to accept at face value RC sttements about so many
heretics that they were orgiastic; demon worshiping; homosexuals etc.
Best wishes
Tim