Corbyloon Yes as you say ''In the light of the guidelines provided by the European Council , the union shall negotiate and conclude an agreement with that State''
BUT the guidelines are made by the European Council WITHOUT the outgoing state !
https://fullfact.org/europe/how-eu-works-leaving-eu/
We can negotiate but ONLY on what was put into the guidelines by the European Council without the UK being present.
I'm afraid the judge, old geezer and others who try, repeatedly, to present reasoned arguments to the lunatics are wasting their time. Casting pearls before swine, as it were.
Once some of these people get an idea (someone else's idea) locked in their brain cell, nothing, short of another bump on the head, can hope to dislodge it.