The Holy Father knows this and if we can't reconcile this group to the Holy See why even pretend that we reconcile sects much, much further away? Just asking!
This is from Rorate Caeli:
Cardinal Müller on the Vatican-SSPX relations: Holy Father wants us to move forward with tenacity
Katholisch.de [Official Website of the German Bishops' Conference]
August 3, 2015
Exclusive: Cardinal Müller in an interview with katholisch.de [excerpt]
Question: It has been strikingly quiet recently regarding the Society of Saint Pius X. Are the attempts to find an agreement suspended or postponed?
Mueller: Regarding this question, there is no substantial new development. The Holy Father wishes that we keep trying: “con tenacia e pazienza” – “with decisiveness and patience.” The precondition for a full reconciliation is the signing of a doctrinal preamble in order to guarantee a full agreement in the essential questions of the Faith. In the past months, there were encounters of different ways which are meant to strengthen the mutual trust.
[Translation kindly provided by Maike Hickson.]