Yup. When I was rebooked to fly the next day, the agent was in such a hurry that she did not complete the rebooking process. When I tried to check in on the same day, I got a boarding pass with "SB" all over it. When I went to ticket counter, I was told that a mistake had occurred but she would fix it and check me in. Apparently, all my 3 VDBs were recorded in PRN, so when she finished reading my file, she said if I wanted to VDB again (I assume she was joking). We had a lovely chat for 15-20 minutes as she was doing a lot of typing. Finally, she said, "there is no M class available at all, I can't rebook you into anything. And I am already 20 minutes past my job time here..." In 30 seconds I got my BP with C as booking class. 2 days later I got my 11700 miles onto my account :-)
Conclusion: talking to people with smile earns 1800 EUR and free miles.