We are not facing a heresy. One cannot say in correct, exact, precise terms that there is a schism [here]. There is a schismatic attitude in the consecration of bishops without a pontifical mandate.
They are inside the Church; there is only lacking a full, a more perfect -- as was said in the meeting with Msgr. Fellay --a fuller communion, because there is communion (http://qien.free.fr/20051113_hoyos.htm).
...
Unfortunately, Msgr. Lefebvre went ahead with the consecration and hence the situation of separation came about, even if it was not a formal schism (http://www.30giorni.it/us/articolo.asp?id=9360).