Disadvantages to rim brakes:
1) They're too light.
2) They're too inexpensive.
3) They're too reliable.
4) They might take one revolution to wipe the rims clean before they start working. That's almost a second at slow speed.
Advantages of Disk Brakes:
1) They have a lot of added complications.
2) They have a lot of really good weight.
3) They always drag on the disk and add some additional drag so that you can build your leg muscles faster.
4) They are expensive.
5) You need special forks and frame to mount them or add some nice heavy brackets.
6) They can take a full revolution to wipe the disk clean before they start working - this might be a full second at slow speeds.
7) They are all non-standard so finding parts is always a fun adventure.
Seems to me that disk brakes pass all of the OCP requirements with flying colors.