Great article, really useful to have all this information in one place, though quite why Unity never got around to documenting it themselves in anyone's guess.
One very important point, that I don’t remember seeing in the article is that frequently you MUST restart Unity editor in order to have its menus reflect changes to priority orders! At least this is true in my experience today ( unity 2017.1) if you are dealing with having hierarchical sub-dividers showing up in the Window Menu.
Its rather inconsistent though. Menu items update reliably when not using priority values and sometimes when you introduce a new one, however sometimes they don’t. So if you’ve made changes and Unity fails to update the menus correctly, try restarting Unity.
Might be nice to add this as a note to the priority/sorting section.