If the purpose of using a PHP template engine is to separate your page structure (HTML) from application logic (PHP), it seems strange that so many other template engines allow the HTML code to include instructions that can alter the output of the PHP code. With PHPTemplateLayer, all control of template output remains with the PHP code, meaning that template tags are clean and easy, no new security concerns are introduced, and you don't need to learn a new language to use it. PHPTemplateLayer is possibly the easiest PHP template engine to install, setup and learn.