The chance of operational upgrades is a frequent point of discussion on this thread, so given I just finished my last KL segments of the year I decided to run the numbers.
All numbers are purely KL, I fly AF very rarely. All tickets are in economy, either standard or light fares (no flex). A majority (~70-80%) of travel is on business bought through a CTA. Personal travel is booked directly with KL,
All segments are short haul.
Numbers are 2022-23.
Total # segments: 164
Total # op-ups: 10 (6.1%)
Segments operated by KL Cityhopper (excluding german airways): 132
# op-ups on these segments: 8 (6.1%)
Segments operated by KL Mainline: 27
# op-ups on these segments: 2 (7.4%)
Segments inbound to AMS (all operators): 81
# op-ups on these segments: 1 (1.2%)
Segments outbound from AMS (all operators): 83
# op-ups on these segments: 9 (10.8%)
Overall I think a success rate of 6-7% is fairly decent - after all these op-ups only happen in oversold situations.
I was always under the impression that op-ups are handled by the gate agent, not centrally by "the computer". And this data does suggest that a KL employee at AMS is substantially more likely to give priority to a Platinum member, compared to an outsourced ground handler at an outstation.