Well, add this to the fire. CHQ just announced a new crew base (large for them) in ORD. This is for "additional and/or changing United flying" with no decrease in the IND base. I know that United LOVES the 170. Most of the teething pains associated with the new type are taken care of (not all, but most) and the performance of the planes is close to where they want and improving daily.
I'm sure the flames will start, but I am just passing the info.