jsblocks observable each() view issue

jsblocks.js

App.View('Navigation', {
    options: {
        url: AppPath + 'views/navigation.html',
    },

    // the current path as an array of URL parts
    currentPath: blocks.observable(['Home'])
});


App.View('Tags', {
    options: {
        url: AppPath + 'views/tag.html',
        route: AppPath +'tag/{{tag}}'
    },

    // fires when route is called
    routed: function (params) {
        App.Navigation.currentPath.removeAll() // removes all items if I log App.Navigation.currentPath
        App.Navigation.currentPath.addMany(['tag', params.tag]) // seemd to add just the one new value
    }  
});


// now the Tags.html
// With each route change, the new li elements are added, but the old ones arent removed. 
// If I mouseover the ul, then the li are removed from the DOM one by one until only the correct output remains. 
<section data-query="view(Navigation)">
    <ul id="breadcrumb" data-query="each(currentPath)">
        // I spotted another debug error
        // this line throws out render(false) - object specified where boolean expected   <li data-query="if($view.currentPath.length - 1 == $index, render(false))" data-id="28">
        // as well as the if($view.currentPath.length - 1 == $index, ?, ?) - less arguments than the required specified bug you already know about
        <li data-query="if($index == 0, render(false))"> / </li>

        // this renders fine and prints out tag, value
        <li>{{$view.currentPath}}</li>

        // prints 2, but prints 0 after pushstate to a tag/different param route
        <li>{{$parent.currentPath().length}}</li>

        // because the above prints out the correct length, I expect the following to work as well
        // throws 'Uncaught TypeError: Failed to execute 'contains' on 'Node': parameter 1 is not of type 'Node'.' after pushstate
        // I presume this is related to .currentPath().length now being 0?
        <li data-query="if($parent.currentPath().length -1 == $index, render(false))">{{$this}}</li>

        // when this present without the two data-quries above, it causes the duplication behaviour
        <li>{{$this}}</li>
    </ul>
</section>