Witton Park; It's rubbish, any "special arrangement" would be the backstop in everything but name and the DUP would never accept it.
In summary.
Mays' deal - No border.
Norway type deal - No border
No Brexit - No border.
Crash out - Border.
Deal without the backstop - Border.
So if the EU and Varadkar backdown then we end up with a border and all the social and security turmoil that will ential.