gistfile1.js

// some non-working in-theory code
dojo.declare("Tabs", dijit._Widget, {
	
	postCreate:function(){
		this.controller = dojo.create("ul");
		dojo.place(this.conroller, this.domNode, "before");
		this._scanChildren();
	},
	
	_scanChildren: function(){
		dojo.empty(this.controller);
		this.children = dojo.query("> li", this.domNode).forEach(this.addTab, this);
	},
	
	addTab: function(n){
		var t = new TabChild({ linked: n, parent: this }, dojo.create("li")).placeAt(this.controller);
	}
	
});

dojo.declare("TabChild", dijit._Widget, {

	postCreate: function(){
		this.connect(this.domNode, "onclick", function(e){
			this.parent.children.removeClass("showing").filter(function(n){ 
				return n == this.linked;
			}, this).addClass("showing");
		});
	}
});

dojo.declare("TTabs", [ dijit._Widget, dijit._Templated ], {

	templateString:"<div><ul dojoAttachPoint='controller'></ul><ul dojoAttachPoint='containerNode'></ul><input type='hidden' dojoAttachPoint='valueNode'></div>",
	
	postCreate: function(){
		dojo.query("> li", this.containerNode).forEach(function(n){
			new TabChild({ parent:this, linker = n });
		}, this);
	}

});

<ul id="foo"><li>blah</li></ul>