Yet another topic that is listed on the blueprint so I'd better be prepared for it. I don't plan on going into much detail as I think the odds are pretty low that I would see anything on this.
The 24 and 48 port 4G modules support over-subscription. Here is a table from the SAN OS guide:
I don't have any 4G modules in my lab. I might spend a few minutes when I have rack time to try some of the configurations. It looks to me like this isn't worth spending much time at all on.