Yes, it started with the 737's leaving the fleet. People say frequency over mainline, but it's not really true. ORD-MSP was every hour on the hour with mainline, now it's 50/50 regional/mainline. Like ORD-BOS, UA had 10 flights a day mainline, now slowly, regional is replacing mainline, not just filling in. Along, with LGA, ATL, DFW, etc. The day will come that ORD-LAS-PHX-LAX will go Express. To me, I see smaller aircraft, same number of flights, less passengers, as others have jumped ship. Every week I'm on a WN flight with some former UA 1K, tired of delays and cancellations. All my Chicago-Midwest travel has gone to WN, and trust me, I'm not alone....