I don't. The only reason I heard about it was because I happened to be playing when the dev hopped on and started messing with people. Someone asked him about architecture and they said they use two websockets to prevent congestion.
I'm skeptical about the design, but the only way to know whether it's effective is to measure it.
Carmack's great breakthroughs came from trying every logical possibility and then sticking with the ones that worked. There were dozens of dead Quake designs that no one knows about, e.g. beam trees.
One mistake I made in the early days was to go around asking people what to do or how to design something. The truth is, no one really knows the best way to design anything. The only thing you can do is think of possibilities, try them, and ruthlessly measure whether they're effective. Often the most effective designs come from unexpected combinations, which is why this dual websocket idea is worth taking seriously.
One nice property is that if it does work, it only costs 2x bandwidth. Realtime games' bandwidth grows as O(n^2) with the number of players (e.g. 90 players need updates about all 89 other players plus themselves). So doubling the bandwidth isn't a huge cost.