FK, you will find this comment by Fr. John Romanides, an eminent and recently deceased Orthodox theologian, informative on the subject we have been discussing.
http://www.orthodoxinfo.com/inquirers/frjr_sin.aspx
Thank you for the link. I didn't read the whole thing, but I did see a few statements that raised my eyebrows. Father Romanides was no potted plant. :) For example, I noted him saying "Thus, according to St. Paul, creation as it is is not what God intended it to be— ...". You know what kind of buttons that presses with me. :)
In the passages I read, he seems to spend most of his time on Paul in this writing, and quite a lot of time discussing satan. It seemed to me that his idea was to peg satan with the blame for man's sin as sort of the Orthodox version of, or response to, the doctrine of original sin. I.e., man sins because of satan, not because of Adam.