This CC demo tells you which combination of ESC, mode, battery, and motor will enable the ESC to provide "proper governing". You may need a later version than you have to run the demo (I used V3.26.0). Thanks to Steve Rogers of CC for talking me through this!
1. Boot up CastleLink -- with no ESC connected
2. CastleLink notices that you don't have an ESC connected and asks: "Device you are trying to Link". This allows you to choose among many different CC devices, including the Phoenix 10, 25, 35 .. etc., as well as the Phoenix ICE Series, which I chose to study.
3. click on "Demo mode"
4. In the "Vehicle type" window, put in "Control Line"
5. Choose which setting for CL Governor Mode that you want: High RPM, Low RPM, Simple, and Set RPM are available with the Phoenix series. I chose High RPM.
6. Choose your battery type: Click on "Calculate Battery Voltage" and adjust for LiPo 3S, 4S, 5S, etc.
7. Choose your motor gearing: Click on "Enter Motor/Gearing Info" -- you can probably keep the default value, which is 1 to 1 (outrunner motors).
8. Enter your motor number of poles in this same "Enter Motor/Gearing info" window.
9. Now you can choose any RPM and the program will tell you if it is in a suitable range for governing. If not, it will tell you "Too slow for proper governing" or "Too fast for proper governing"
10. You may try switching any of the motor or battery or RPM information and see what it says. It gives the % of throttle required to give the RPM (if in the "proper governing range") as well as the pulse width value in milliseconds (what "timers" provide).