Flew DCA-EWR-FLL yesterday.
Asked for a SDC at the ticket counter. They were happy to oblige and in the middle of their efforts I got a call; needed to stick with original itin. Took some effort on their part but they got me back on my flight and--more importantly--snagged my upgrade back (same seat).
DCA-EWR delayed by an hour on tarmac, meaning I would miss connection. Yeah, it took 35 mins to get a rep on the Premier line (what else did I have going on sitting on an RJ?), but she got me booked on another flight and confirmed in F. CS agent at EWR got me the seat assignment I wanted for EWR-FLL in two seconds. Ironically, I ended up on the same flight to which I tried to SDC.
All in all a positive experience for me despite the hold time. I felt I got great service as a Gold flyer. And my CPU ratio is about 86% so far this year. YMMV. For now I'll stay optimistic that this is a sign of things to come.