Not sure if this would work on Twenty Eleven but we do have it working on our theme using widgets placed in a header area (no PMPro functionality involved). We created 2 different versions of the menu, one with the member-only link, one without. Each menu is placed in its own Custom Menu widget in the header. We’re using the Widget Logic plugin to control which menu is displayed – e.g., if (current_user_can(‘subscriber’)).
You can also use the pmpro_hasMembershipLevel() function to check if a user has a membership level or not (vs just being a subscriber).
Here is the code in the MemberLite theme that decides which menu/etc to show: https://github.com/strangerstudios/memberlite/blob/master/header.php#L77
Doesn’t have to be as complicated as that, but it should give you an idea.
