The Chicago wye is actually quite busy. The Metra BNSF line uses the north leg of the wye, and BNSF Freights, and Amtrak use the south leg. I believe there might be some other class ones using the south leg of the wye. I know NS has a customer inside the Amtrak yard that gets an occasional local as well.
I mean in theory if they wanted to make the 27/28 turn easier there is a way that involves no backup moves. If you would drop down from Vancouver into Albina Yard you could actually come across the Steel Bridge and be turned around. Now that being said Albina Yard doesn't have a passenger bypass track like the BNSF Portland Yard.
The New Orleans wye is inside the shop complex.