You're totally correct that the performance is terrible when the actual network characteristics are something that the algorithm's "prior assumptions" thought w

You're totally correct that the performance is terrible when the actual network characteristics are something that the algorithm's "prior assumptions" thought was impossible. We think the same is true of traditional TCP. (For example, traditional TCP assumes that in-network buffers will be small, and therefore that it's acceptable to keep filling them until they start dropping packets, without harming delay-sensitive cross traffic too much. Today's Internet no longer matches TCP's implicit model, and the consequences are that you can't upload to YouTube and use Skype at the same time on a consumer Internet connection. We think it's better to at least make the assumptions explicit!) In the second paper (now posted), we have improved the initial results in that we can now train a RemyCC that outperforms TCP CUBIC-over-sfqCoDel over a 1000-fold range of link rates (instead of 10x in the first paper). But the same basic point still holds.