“The reason we can’t receive Holy Communion together is because the Church of Rome teaches that our Anglican ordinations are invalid: “absolutely null and utterly void,” as the tactful wording of the Papal Bull puts it.”

Wrong. It’s because Anglicanism rejects transsubstantiation, and it is not faithful to receive communion from a church while rejecting what that church teaches about it; whereas if one did believe in transsubstantiation, the consistent thing to do would be to accede to that church. 
As for the monarch of England marrying a Roman Catholic, that would really only make sense if they agreed to bring up their children as Catholics; and this would likely lead to the Supreme Governor of the Church of England being a Roman Catholic. Can’t Bishop Gledhill see this?

I was talking over the proposal to remove the prohibition of royal marriage to a friend this evening here in London (disclosure:  we are both RC).  It dawned on us that there is something of a split between the inherent nations of the United Kingdom.  The Scottish cardinal has attacked the prohibition, and called for its repeal.  The English bishops have (as far as I can recall) said very little, and seem to be largely uninterested in the issue.  But then, a kind of visceral anti-Catholicism is still found in the more tribal parts of Scotland and, though diminishing, where it exists tends to be from the poorest segments of the working class.  By contrast in England anti-Catholicism is found more in the media, and in a liberal middle-class elite.  At times (eg the attack on church schools by the Labour government) we feel the heat but generally in England anti-Catholicism is a thing of the past.  Even Ian Paisley over in Northern Ireland has simmered down.