If you create an item in the navigation menu with a sub-menu, there is an option to "Hide this item from... {groups}".

This should be changed to be "show this item to {groups}" for logical reasons. If you have a member who is in Group A and also in Group B (secondary) and you want to show the menu item to Group B, but not necessarily those in Group A, it doesn't work if your member is in both groups.

Everywhere else in IPS the logic is to include groups rather than exclude them when it comes to granting permissions.

It used to be set to "Show to selected groups", however if you go to the Manage Applications area (or edit a tab from the same area you are referring to that belongs to a default application), this area is based on "Hide from groups". Thus, for IP.Content to configure custom tabs based on "Show to groups" ultimately results in an inconsistent configuration experience when configuring one tab vs another.

Wouldn't it be better to allow the Admin the option to chose which method they would like to use? Right now it doesn't work the way I think it should.