There is no need to call names. Whether you agree or disagree with him, he is an educated man, and not a moron.
Additionally, the German bishops appear to be in the wrong, and the Prefect for CDF is right in telling them so. Abp. Mueller is also the one trusted to reinforce the perpetual teaching of the Church, as found in the Gospel, (Mark 10:11, Luke 16:18).
Rome tends to move very slowly, so it will interesting to watch how this is handled.
Tell that to the Franciscan Friars of the Immaculate.