The Church has always taught that to receive Holy Communion whilst in an adulterous relationship is in itself mortally sinful. How can there be any compromise on this, it is either a sin or it isn't?
If the Pope is saying that under certain circumstances it is not sinful, he is changing a teaching, a doctrine of the Church. He has, through Cardinal Schönborn Archbishop of Vienna, insisted that there is no doctrinal change.
It is vital that he clears this up.