Thus spake "Sean Finn" <seanf@routescience.com>
Chasing the last ms of optimization tends to both focus traffic on the single "best" link, as well as increasing the rate of route change as the "best" continually changes.
Considering alternate paths with roughly similar performance significantly changes the picture. This not only reduces the required rate of route change, but also tends to spread the load across the range of valid (near-optimal) paths, and thus significantly mitigates the concerns raised in the paper.
The problem is eliminating the possibility of a packet taking a "near optimal" path from A to B, and then taking another "near optimal" path from B back to A. I suspect this is impossible to fix while retaining hop-by-hop routing. S