Is this documentation still up to date?

"Updating the global template for a built-in block
Say you want your autonav block to always use DIVs instead of list elements. Instead of updating blocks/content/autonav/view.php (which would then be overwritten when an upgrade occurs), create blocks/autonav.php in your root web directory. This template will then automatically be used by your autonav block."

It's either not working form me or I'm making a silly mistake. Is there a more detailed section of the documentation that talks about this?

Thank you.