Judging whether an individual Protestant is a heretic or not would have to made on an individual basis, and only the Church herself can make such judgments, which she is no longer making, at least on a formal, public basis. Ditto for the schismatic Orthodox. Is heresy or schism grave sins? Per the Catechism of the Catholic Church and 1983 Code of Canon Law, they are:
Are you saying that the Church's statements in Councils past are abrogated?
No, although some statements are disciplinary:
CANON 29 -- "We forbid under penalty of anathema that that deadly and God-detested art of stingers and archers be in the future exercised against Christians and Catholics." (Second Lateran Council)
http://www.fordham.edu/halsall/basis/lateran2.aspYet Schism, although Protestants are schismatics as are the Orthodox, is an act which not every member of those sects has reasonably committed until he has undergone the mental process of choosing error.
Agreed.