I think they do a bit more deduction than you think, like:
P1) The Bible is the literal inerrant word of God.
P2) Science generally works in making advancements (so we cannot deny it outright)
P3) Some science contradicts what the Bible says.
C1) Since the Bible cannot be wrong, then there must be something wrong with the science that contradicts it.
C2) Since only some of the science must have something wrong with it (and we cannot deny it all), then there must be some difference between the science that contradicts and the science that does not.
They keep getting pushed back into a corner, because the questionable science that may contradict the Bible gets more and more undeniable. Also, most of the "claims" from the Bible that are wrong are about things in the past, so they end up with the distinction between good and bad science having something to do with claims about the past.
And viola -
Historical science is the problem! Yeah, that's sounds right!
And then that's when the circle-jerking that you've noticed comes into play.
Edited by Catholic Scientist, : No reason given.