After clicking on "Hosts" and performing a search based on the criteria I'm looking for:

I get a result of 8 hosts.

I click "Toggle All" and verify that the hosts are checked. (8 hosts in this particular case)

I click "Edit Multiple Hosts" and the following page only shows 1 host.

When I apply a new hostgroup to "all" hosts, and go back to the hosts list to confirm, the change is only applied to the one host.

TheForeman v. 0.2