Must Differences in Cognitive Value be Transparent?

Frege's 'differential dubitability' test is a test for differences in cognitive value: if one can rationally believe that p while simultaneously doubting that q, then the contents p and q amount to different 'cognitive values'. If subject S is rational, does her simultaneous adoption of different attitudes towards p and q require that the difference between p and q (as cognitive values) be transparent to her? It is natural to think so. But I argue that, if attitude anti-individualism is true, then rational differential dubitability does not presuppose that differences in cognitive value are transparent. The significance of this argument lies in what it tells us, both about the notion of cognitive value and its relation to the differential dubitability test, but also about the prospects for a Burge-type position which aims to combine attitude anti-individualism with a (qualified) reliance on the differential dubitability test.