[theme-reviewers] Custom implementation of required hooks

[Konstantin Obenland]

I have a question concerning wp_link_pages().
In the codex, the function is listed under "Required Hooks and Navigation" (http://codex.wordpress.org/Theme_Review#Required_Hooks_and_Navigation).
Would it be okay for a theme to provide the same functionality, but with a custom implementation?
In this case it's echoing it as an unordered list, which can't be achieved through passing arguments to wp_link_pages().
   
Looking forward to your insights,
Konstantin