Right - it does. My point was that Quic still has 2 layers which determine the amount of data that is sent to peers. On the lower level, there is a congestion c

Right - it does. My point was that Quic still has 2 layers which determine the amount of data that is sent to peers. On the lower level, there is a congestion controller - which can be like Cubic, New Reno, BBR, etc. This part does not know anything about Quic streams yet. On a higher level you have the Quic streams, which carry user data. These are subject to flow control windows, and there also exists a shared per-connection window. Depending on the implementation the layers might not be very much aware of each other, which can also lead to imperfect utilization. That said the situation is obviously still different than with TCP, since the congestion controller does not limit the amount of user data but packets in general (which includes retransmits, etc). So the outcomes will certainly be different than what we observe with HTTP/2.