Hello JM,
I did a series on this in my blog:
Critique. This should be helpful. However, when Bahnsen argues that rational inquiry can be accounted for in his worldview, he is thinking that only his worldview can make rational inquiry intelligible. All other worldviews fail including non-Christian theistic worldviews. Of course, this is never demonstrated in any particular apologetic encounter. Rather, all that is demonstrated is that the worldview before him cannot account for some precondition for knowledge while his can.
Brian