I had to work in a extremely old project, and needed to disable the View Renderer. It’s a quick one, if you know how to do it, so for later use and your convenience, hereby.

Do it by adding the following code to your Controller’s preDispatch method:

<?php
public function preDispatch () {
    $this->_helper->layout()->disableLayout(); 
    $this->_helper->viewRenderer->setNoRender(true);
}