Q:

Do all Backbone methods need to be bound to this?

In every method, that I use this and want it to point to the object, do I need to use _.bindAll().  If not, in what cases do I need to use bindAll()?
var AccountView = Backbone.View.extend({
    Name:                 'AccountView',
    P: {
        pictures:         $A.Reg.get('path_pictures'),
        images:           $A.Reg.get('path_images')
    },
    E: {
        hold_name:        '#hold_name',
        hold_pic_small:   '#hold_pic_small',
        hold_pic_large:   '#hold_pic_large'
    },
    initialize: function () {
        $A.morph(this.E, $A.el);
        _.bindAll(this, 'render');
        if (_.isObject(this.model)) {
            this.obj = this.model;
        } else {
            this.obj = this.model.toJSON();
        }
        this.render();
    },
    render:  function () {
        var time = new Date().getTime();
        this.E.hold_name.innerHTML = this.obj.name;
        $A.el('#p' + this.obj.privacy).checked = true;
        if (this.obj.picture === 0) {
            this.E.hold_pic_small.src = this.P.images + 'generic_small.jpg' + '?_time=' + time;
            this.E.hold_pic_large.src = this.P.images + 'generic_large.jpg' + '?_time=' + time;
        } else {
            this.E.hold_pic_small.src = this.P.pictures + this.obj.h_file + '-1.jpg' + '?_time=' + time;
            this.E.hold_pic_large.src = this.P.pictures + this.obj.h_file + '-2.jpg' + '?_time=' + time;
        }
    }
});

A:

Cases where you need to bind the method to the Backbone class:

AJAX callback
Model success callback
DOM events listeners
Global events listeners

Cases where you don't need to bind:

methods invoked internally in the class in this way 'this.someMethod();' because you are already on this.
event listeners in the event hash of the Backbone class. (delegateEvents automatically bind them to the class).

For example, in your case, you don't need to bind render, as it is called as this.render and you do not have any other listener that would cause render to lost the scope. 

