Greetings,
A final note. Most HFC Systems designed today are less then five amps deep and as our cascade is reduced so to is their concern for the unity gain. I agree with your assumption that all pad slots of active legs need to be filled. Even when forward rf/output leg is terminated the return signal is traveling from the input port of your location and has the complete return side of the module involved before it ever reaches the terminated output rf port.
Petergunn.
