W3 total cache NOT purging when saving updating deleting posts

Question

I tried all settings, nothing worked.

I now do the following in my functions.php:

add_action( 'save_post', 'wpse41912_save_post' );
add_action( 'delete_post', 'wpse41912_save_post' );
add_action( 'trash_post', 'wpse41912_save_post' );
function wpse41912_save_post()
{
  w3tc_flush_posts();
}

That seems to work.

Why does W3 total cache not deliver what they promise in their settings?
Pull the plug on W3 total cache generally?