This is based on her presentation and some dinner conversation at HPTS 2019, so I don't know if there's actually a paper I can point to. The gist of is that Paxos normally involves an arbitration phase where there are conflicting proposals, which adds a second pair of message delays. But if you relax the consensus problem to agreement on a set of proposals, rather than a single proposal, you don't need the arbitration phase. Instead of "who won", it becomes "everyone wins". Then you can impose an order on that set via, say, sorting, and iterate to get a replicated log.

I read over bits of Elle; the documentation in it is absolutely top-notch. You and Peter Alvaro knocked it out of the park!

Thank you! Could I... hang on, just let me grab reviewer #1 quickly, I'd like them to hear this. ;-)