I dont know if having an .php extension actually hinders your search engine listings.
Regarding bad PHP-search-engin I heard rumors, too, but imho the rumors are not true.
- go to google
- enter "Template engine site:php-coding-standard.de" and search
You will find my PHP site: "php_template_engine.php" (as you can see extension: "*.php")
If you really want to just put out static code (I would not recommend it), you could use
tmpl->grab();
Regards,
Claus