I find it weird to document it as ``@return $this``, as ``$this`` is not a PHP type. And it is not either a type supported by PhpDocumentor: http://www.phpdoc.org/docs/latest/for-users/phpdoc/types.html

PhpStorm 7 introduces the support for ``@return static`` to document that it returns the same class than the caller (with the same meaning that the ``static`` keyword in PHP, so being consistent with the way PhpDocumentor specifies the ``self`` return type)