Wireless: Difference between WPL and Groups

In Freespeak II Configuration Editor, what is the difference between a WPL and a Group?

WPL A WPL (wireless partyline) is just like a wired PL ring. So the partyline is made and each beltpack that wants to be a member has a (default for FSII) Talk& Forced Listen key assigned to it. So whenever a beltpack talks on WPL1, any beltpack with that key will hear them. Beltpacks without that key will not. Interfaces like PLCHA or the 4w ports have to be added toWPL as members because they don’t have physical FSII keys. So e.g. A 4w port added as a member to a WPL is essentially the same as having a beltpack with an always latched talk & forced listen. Whether the device talks or not is controlled externally to the system.  
Groups  The easiest way to explain a group is to use the example of a manager talking to three of his team. The three team members are added into the group and the manager only gets a group key. Then the manager can talk to the group but the team members can’t talk to each other. The manager will show up on the reply key so if a group member wants to talk back they can press reply to set up a one-to-one path with the manager. That said , we have seen FSII users create a group and just put every pack in and then give every pack a key for the group. This then approximates a partyline.