I think what you are saying is correct.
Maybe some examples will help clarify what happens. For this example:
• the team has two physical ports
• the server has three virtual machines, VM1, VM2, and VM3
Both team types provide fault tolerance so that the load will be balanced across working ports if one or more member ports fail.
Let’s look at a VMLB team. VMLB teaming mode was created specifically for use with Hyper-V. Let’s say that VM1 has as much network traffic as VM2 and VM3 combined. The VMLB team balancing algorithm will analyze the traffic and assign each VM to only one team member port. So VM1 would be assigned to member port 1 and VM2 and VM3 would both be assigned to member port 2. Thus the networking traffic would be roughly balanced between the member ports.
• VM1 -> Port 1
• VM2 and VM3 -> Port 2
Next is an example of using ALB. You can see details of ALB in the paper at http://www.intel.com/network/connectivity/resources/doc_library/white_papers/254031.pdf. The ALB teaming mode balances transmit traffic across connections between the server and the other end of the connection based on destination IP address. Each new data flow is assigned to the least loaded team member. All the virtual machines share the ports based on the destination address.
In the paper I referenced above, you will see reference to Receive Load Balancing (RLB). When Hyper-V is not involved, RLB is enabled by default. With Hyper-V, Receive load balancing (RLB) cannot be enabled, So you need to use VMLB mode if you want to have a distribution of receive traffic for the team and VMLB is the recommended load balancing team mode for use with Hyper-V.
I hope this helps.