None of what you said is true regarding Capacity Plus. Capacity Plus subscribers do not affiliate. The talkgroup/site associations are defined in the Master repeater codeplug (or set to all wide area).All the sites will not carry all the traffic in the system. A radio has to be in the area of the Site you are monitoring and affiliate to the site. Once they talk, their conversation will only be heard on sites that have users affiliated to that group.
Source: run two different three-site Cap+ systems.