dojo destroy best practices

require(["dojo", "dojo/parser", "dijit/registry", "dojo/Stateful", "dojo/_base/connect",
"dijit/form/Button", "dojox/widget/Toaster"],
function (
    dojo, parser, registry, Stateful, connect,
    Button, Toaster
    ) {

    connect.subscribe("/load", function () {
        var stateful, t, tokens, toaster;

        stateful = new Stateful();
        tokens = [];

        toaster = new Toaster({
            positionDirection: 'bl-up',
            duration: 500
        });

        t = connect.subscribe("alert", toaster, "_handleMessage");
        tokens.push(t);

        t = connect.subscribe("/unload", function () {
            registry.toArray().forEach(function (w) {
                w.destroy();
            });
            dojo.forEach(tokens, connect.unsubscribe);
            delete stateful;
            stateful = undefined;
            delete tokens;
            tokens = undefined;
            toaster.destroyRecursive();
        });
        tokens.push(t);

        t = connect.subscribe("CreateWijit", function () {
            var w = new Button({
                id: "myButtonId",
                label: "myButtonTitle",
                onClick: function () {
                    connect.publish("alert", { message: "myButton" });
                }
            }, dojo.create("button", null, "workArea"));

            //dojo.byId("workArea").appendChild(w.domNode);
            stateful.watch("myButtonTitle", function (t) {
                w.set("label", stateful.get(t));
            });
        });
        tokens.push(t);

        t = connect.subscribe("DestroyWijit", function () {
            var widgets = registry.findWidgets(dojo.byId("workArea"));
            widgets.forEach(function (w) {
                w.destroyRecursive();
            });
        });
        tokens.push(t);

        t = connect.subscribe("UpdateLabel", function () {
            stateful.set("myButtonTitle", new Date().toLocaleTimeString());
        });
        tokens.push(t);

        new Button({
            topic: "CreateWijit",
            label: "Create Widget"
        }, dojo.create("button", null, "controlContainer"));

        new Button({
            topic: "DestroyWijit",
            label: "Destroy Widget"
        }, dojo.create("button", null, "controlContainer"));

        new Button({
            topic: "UpdateLabel",
            label: "Update Widget"
        }, dojo.create("button", null, "controlContainer"));

        connect.publish("alert", { message: "Ready!" });

        registry.toArray().forEach(function (w) {
            if (w.topic) {
                w.connect(w, "onClick", function () {
                    connect.publish(w.topic);
                    connect.publish("alert", { message: w.topic });
                });
            }

        });
    });

    parser.parse();

    window.unloadReload = function () {
        connect.publish("/unload");
        connect.publish("/load");
    };
    connect.publish("/load");

});