In the Clone TV device Adjust Input Settings, select Method 1, edit the input list to have only 2 entries. Call them "Analog Tuner" and "Digital Tuner" for example. Select the cycling/toggle command from the drop-down list. It's probably the "InputTV" command (you need to answer the questions in my post #19).
In the Main TV device Adjust Input Settings, select Method 2 (discrete method), edit the input list to have at least 2 entries (HDMI and whatever you plan to use in the future). Make sure the commands you select are discrete (test them in device mode). Don't forget to set the Clone device Adjust Power Settings to "no power button". It's the main device that will control the power.
Set your activities as follow:
Activity Name....Primary TV Device.......................Added TV device
Watch DVD........Main TV on HDMI input................None
Watch Analog....Clone TV on Analog Tuner input.....Main TV
Watch Digital.....Clone TV on Digital Tuner input......Main TV
Use the Activity add device feature (Yes, but I want to add more control of options and devices for this Activity) to add the Main TV device to the 2 TV Tuner activities. When it ask what input to use for the added main TV device, select "I don't need to set the input on my main TV". Here, all you want the main TV to do is control the power.

Note: The above technique will work properly if the discrete HDMI command does NOT reset the tuner cycling/toggle command. I am still waiting for the answer to my question #3 in my post #19.