> Is it better implemented than the various TCP algorithms we use underneath regular SSH? Perhaps. That remains to be seen.

SSH multiplexes multiple channels on the same TCP connection which results in head of line blocking issues.

> Should you find yourself limited by the default buffering of SSH (10+Gbit intercontinental links), that's called "long fat links" in network lingo, and is not what TCP was built for.

Not really, no. OpenSSH has a 2 MB window size (in the 2000s, 64K), even with just ~gigabit speeds it only takes around 10-20 ms of latency to start being limited by the BDP.