I thought whisper wasn't a channel in of itself thus each member of the whisper group would need to make sure they created a whisper group that included everyone and tab to the app every time they needed to add or remove someone.
Not sure I understand what you mean by nesting. It was my understanding that Guilded's implementation was that all those in Parent Group A would broadcast to all children of the group while those in child group B would hear from Group A but only talk to other members and children groups of group B.
Battlefield 2's way was more akin to how
@marcsand2 using two programs one for each ear and then hotkey the push to talk on that channel to different buttons. This allows each channel to be focused on a specific topic. As a squad member having com's overrun with needless command tactics is frustrating when you are attempting to work together sweeping rooms or holding a control point. Thus is typically better to not go with a nested approch and allow each squad to have their own channel while the squad leader can be in two channels the squad channel and a leadership channel.
lol, even with strick com discipline its been my experience when playing competitively the channel get heavily utilized.