I'd like to use a Bootstrap popover (from Angular-Bootstrap) to modify a model value on the $scope of a controller.  It seems that the popover template is breaking some connection.
I made a small example to show my issue:
Directive 1 (master-directive) takes in the model as an isolate scope property.  It's template is a button that displays a popover.  The template for the popover shows directive 2 (sub-directive) which is fed the model value through an isolate scope property, and would contain some sort of UI control to modify that property (in the demo, this is just a mouse click).
Normally the changes would propagate back up to the controller (sub-directive model is two-way bound to the master-directive model which is then two-way bound to the controller model.  However, when the template that contains sub-directive is used in the popover, the two-way binding between sub-directive and master-directive is broken.  Any changes to the model in sub-directive will stay local to that directive, and are not propagated upwards.
Relevant Plunkr: http://plnkr.co/edit/3ZnmNUtajXsAHJjCdkkJ?p=preview
Here is the same Plunkr without the popover, demonstrating that it works: http://plnkr.co/edit/Mr4djvZCVpEUkgDZpyvV?p=preview
Is there a step I am missing to bridge the gaps that are introduced with the popover module?
 
     
    