While I agree that perhaps Birgitte should have been asked about stuff, I do think it's unrealistic to assume that she'd be a huge font of knowledge that just so happens to have the answer to every problem our heroes are facing.


For example, we know that she died before the sealing, and so she definitely has no information there.

There were large numbers of shadow-aligned channelers in the WoS - why is is fair to assume that Birgitte has an intimate knowledge of the specific thirteen that managed to survive?

For that matter, Birgitte thinks of herself as a "simple archer." What if she doesn't know the intricacies of the Shadow's attack strategies? And even if she did, who's to say that they were the strategies favoured by Demandred and Ishmael, who are the only major leaders left. What if she had no real care to learn about how attack weaves really worked, as a non-channeler? Maybe she has no real knowledge of how shock lances work, just that they did. Would she know the male part of the Song, and would it even matter with no Nym left?