In 1971, Roman Catholic theologian Hans Küng published his Infallible? An Inquiry in which he declared his opposition to the doctrine of papal infallibility. This represented a very vocal apostasy from a core Catholic doctrine by a man who occupied an influential position as professor of Catholic theology at Tübingen. Küng was not excommunicated but was stripped of his missio canonica, the licence to teach as a Roman Catholic theologian. He was able to remain at the university as professor of ecumenical theology, however.
In 1983, the Code of Canon Law revised its statement on excommunication: no longer did it sever someone from the Church. Excommunicated Catholics are still Catholics. At no point does it cancel the sacraments — Catholics readmitted into communion are not required to be re-baptised, which is impossible anyway, given the Catholic theology of baptism. Of course, in Küng’s case this was all moot anyway. Despite his heresy, he was not excommunicated.
I point this out for two reasons. First, to remind readers that excommunication in a Mormon setting is the nuclear bomb of Christian excommunications in that it cancels the saving power of the sacraments. When you have the beating of the Catholics in the severity of your censures, it should give you pause. Second, excommunication for heresy is a rare thing in Christianity today. I do not mean to suggest that Mormonism needs to follow Catholicism in its modes of discipline, just that we should recognise the incredible significance of what is being proposed when we speak of excommunication.