Here is a reasonable assessment of a scientist about what she can do (from Janet D. Stemwedel):
… to say an awful lot about the research projects I have completed (although perhaps a bit less about them when they were still underway).
to say something about the more or less settled knowledge, and about the live debates, in my research area (assuming, of course, that I have kept up with the literature and professional meetings where discussions of research in this area take place).
to say something about the more or less settled (as opposed to “frontier”) knowledge for my field more generally (again, assuming I have kept up with the literature and the meetings).
One could listen to this person without enforced interest.