I noticed that when I have a Mirror modifier in the model, parts that are hidden show a greyed wireframe in wireframe display mode.
Then I noticed that if I don't have a Mirror modifier, the hidden parts are completely hidden.
I think it would be useful to have that kind of feature without needing to use a Mirror modifier.
i asked one of the devs and he replied: "that's a bit unclear for me, face could be hidden but edge not"
sounds like it can't be done in wireframe mode in terms of interface design...
I'm sitting, waiting, wishing, building Blender in superstition...