I dont really see any huge evidence of Pre-DM status being implemented. Last week, I flew SFO-JFK (i know it's a small cabin and a high demand market), and I was #5 our of 10 on the upgrade list. I find it hard to believe that there are 4 other DM-qualified individuals on higher fare classes (I was LUT)

on my way back, i was upgraded 5 days prior, but the flight took off with 1 empty BE seat JFK-SFO, so obviously the loads were low.