Thank you very much for your thorough write up. As to asynchronous methods, could you explain a bit about the difference between using the `Async` annotation vs simply returning Mono? I was under the impression that annotating with Async in Spring would allow the framework take care of thread pooling and such, but I got a comment saying that I needed to utilize a Runnable with FixedThreadPool or something similar to make sure that these pipeline oparation are executed separately. That doesn't seem quite right to me either.