But why are you talking about the Oman thing? It's not the reason why he is ban now... At least I really don't think so. There are hundreds (thoussands?) of people who did this thing on GAF or another website, and we didn't heard of a "ban wave" recently...
I think that now everybody who is ban and did the Oman thing feel "omg it's because this Oman thing", but I suppose there is another reason. Or why only them? Why not everybody who did it? With IP adress it's pretty easy to catch everybody and then ban everybody, so why just doing it randomly? :/
And also it doesn't fit with the reasons of the ban.
- "Duplication of purchase" the Oman thing don't "duplicate" anything, if you and your wife both have an account on the 360, and your wife buy Hexic 2 (for exemple) you'll also be able to play this game for "free" on your account, it's not duplicating and so it's not against the ToS.
- "Microsoft Points Fraud"... Well no, he didn't try to earn any MS points by any means, so it can't be it.
- "Illegitimate acquisition of redemption code", he didn't do that either, he didn't use a "fake" code or something...
So it's why I don't feel the reason is the Oman thing.