I've attempted to make the distinction before regarding her being sinless from voluntary sin while still being subject to involuntary sin. My viewpoint was rejected by most. Although in Orthodoxy there is a distinction between the two, most people you find will say that Mary was sinless in both aspects. With that being said, no one will throw you under the bus for believing either. It's not dogma by any means...i.e. to what extent/degree she was sinless doesn't affect our salvation.
It's good to know where the majority seems to stand. But can't anything effect our salvation, depending on our own conscience before God? Isn't salvation at its core a matter of God's judgment of the motives and intents of each heart, as each heart follows Him alone, more than it is a matter of adherence to certain doctrinal standards? I don't know the answer to these questions. I'm relatively new to the orthodox faith.
I do know this much: given my experience in life, I personally would consider it unsafe to my salvation to change my view simply according to what is rejected or accepted by most modern Christians. It seems to me that all peoples, even "God's People," struggle with imperfection. Historically, in the people of God, I see a pattern where there seems to be a smaller remnant that goes against the grain and gets it right more often than the majority. That doesn't mean I've got to try to be a rebel without a cause. However, if my mind and heart sincerely lead me in a direction that is contrary to popular opinion, then I don't worry too much about it as long as my own conscience is clean. This is especially true if the matter is not "dogma" according to holy tradition. In fact, I would even expect such situations to occur as long as there is sin in the world.
Christ said, “If anyone comes to me and does not hate father and mother, wife and children, brothers and sisters - even his own life - such a person cannot be my disciple." I suspect this was said even for us, orthodox Christians, even today, to all of us sinners.
Growing up as a Southern Baptist, I believed all sorts of false doctrines that everyone or most everyone around me believed, very many of them seemingly sincere, good Christians. It took me 15 years to realize I had to walk according to the Word of God and my conscience in the Spirit, not popular opinion, not my families conscience, and not even my "spiritual" families opinion. God only. I was miraculously healed, had a vision of Christ, and believed at the age of 14. However, it wasn't for 15 more years that I became willing to reject everything that everyone had ever told me about God, regardless how many of "them" there were, and just accept what God seemed to be revealing to my spirit. Until I did that I was a Copier more than a Christian. And thank God I finally became willing. He saved me, and brought me to the Orthodox Church.
So... long story short. I'm gonna go with "Mary probably had un-intentional sin."
That's just me. It's not a huge issue for me either. I'm just trying to understand some of the words I'm saying in the liturgy and not just thoughtlessly repeat what I hear.
All that said, I do believe she chose not to sin though. I think that is important. Is that considered dogma?