Can you explain how the change to rule 41 allows the things you say it does? The rule 41 changes don't appear to expand the set of warrants that can be issued except by not requiring the location of the media to be searched to be known if technological means were employed to conceal them. For example, if the Feds knew you were "using an anonymous network in the same city as the one where crime X was committed" and are able to get a warrant to search your devices after this rule change, they would have known which district to get in a warrant in and thus not had any problems getting a warrant prior to the rule change.