1. Who determines what is sinful in obedience? Do I open up my Denzinger and determine it myself? Just look at the Dimond Bros. This is exactly what they do. Look at everyone who purports to be Catholic and is actually interested in their faith. This is what they all do and everyonr arrives at opposing and different conclusions!
2. The authority of the Church, while not being the entirety of the Church, is still the center of and the majority of the totality of its being for without its head, there is no Church.
3. I do not wish to discuss Msgr. Lefebvre's case. Like I said. I don't have the authority.
4. The Orthodox, like yourself, have rejected the authority of the Church albeit in different ways. While they reject the dogma, you reject the practice of the dogma in reality. The faith without the head of the Church is a dead one. It is an ancient tome that is interpreted by each person to his or her own liking and pre-existing dispositions.
Do not over complicate the matter, it is really not at all complicated.
1) See my sig.
2) This is confused thinking, or at least confused communicating.
3) We do not need authority to know right from wrong. What the Church's authorities did (and still do) was and still is wrong, what +ABL did was right. Taken to the extremes, two prime examples of that situation you can use are St. Athanasus and St. Joan of Ark.
4) The Orthodox reject the pope as pope, those of us who are not sede do not. We do deny granting or accepting the conciliar popes' wishes and/or directives that are sinful, we can do that, we must always do that. The people lacking in or without the faith, they say because we deny granting his sinful wishes that we reject him as pope and/or reject his authority. It's been that way since the days after V2 and will remain so long as there is a lack of faith among the accusers.