STM and Shaping are different things
I don't think you are understanding the difference between STM and Shaping.
For NNTP and P2P these types of traffic will be shaped, regardless of how much you download/upload based on the total load on VMs network.
I think I read NNTP and P2P will be restricted to a MAX of 20% of the network traffic.
So yes, usenet users will be affected by this.
Interested to know how SSL usenet and encrypted P2P will be detected though, if anyone can explain?