I just finished Words of Radiance and had a theory I thought I'd present. (I haven't seen anyone else put this one forth, but if I missed it I'm sorry.)
We know that most spren gain sapience as they bond with humans. There are some noted exceptions to this, such as the Nightwatcher and and the Stormfather. In the Stormfathers case, it seems to be due to his being a remnant of Honor. But bonding adds something to the spren in the physical realm.
Could it be possible that by binding with Dalinar the Stormfather will start growing back into Honor? That Honor's splintering will be fixed as Dalinar performs his oath to bind things together?
Along those lines, could the Nightwatcher be a splinter of Cultivation? (And could someone bond with her?)
