Wasting Asset

Just got the New Pornographers' most recent, if not quite new album Together.  Here's what I don't understand.  They are a good band, with a good sound, and an admirably egalitarian ethos. A.C. Newman writes some good songs.

But the times when they really soar and shine is when Neko Case steps up front and belts. She's the secret weapon that makes them into a great band at times. She's the only one whose voice has a lot of meat and texture.  So why is it that there's only one track on the record where she really fronts the band?