Clicking child view and preventing parent view from running dblclick event
I'm not sure what seems convoluted to you. It's a simple piece of code, and if you remove anything from it, it will fail to do what you want, as you noted yourself:


If you remove the debounce, the method will be fired 3 times: once for the single click + twice for the double-click. So you need that.
If you remove the double click handler, then it will be fired in the parent


There is one thing you could "optimize", in the ChildView you could make the dblclick handler do nothing:

var ChildView = Backbone.Marionette.ItemView.extend({
    events: {
        'click': '_addToStream',
        'dblclick': function() {}
    },


This will work, because the dblclick will also trigger click, so _addToStream will be called. You still cannot remove the debounce, because without it the dblclick will trigger 2 click events.

Finally, the ChildView doesn't extend the ParentView, maybe that's a typo, and your real intention was this:

var ChildView = ParentView.extend({