Continuing with Vatican II on anointing of the sick:
The number of the anointings is to be adapted to the occasion, and the prayers which belong to the rite of anointing are to be revised so as to correspond with the varying conditions of the sick who receive the sacrament.
The number refers to the practice of anointing head and hands, I suppose. The current rite for Pastoral Care of the Sick has a wealth of prayers, much of which were new compositions coming from the post-conciliar period. Nobody seems to complain about it.