__monadic
Of course there are people who want a KubeStack that is like OpenStack, for better or worse. That's fine too! We just don't want that to be the ONLY choice for customers.
You said it yourself in another comment on here: "It's never blatant, it's always calls for seemingly good things like extra pluggable points to make sure we don't favor particular solutions. Then it's making sure that any decision is brought to a huge vote by a giant committee that spends weeks arguing about if it's something they should even decide on, etc."
This kind of premature generalisation by committee is what has pulled OpenStack down; a situation from which it is now apparently recovering. CNCF seeks to avoid this, by encouraging projects towards interop but not in mandated ways.
The underlying idea here is that a well-run open source project gets plenty of strong direction from actual users, who must be interacted with directly.
There is a still-forming End User Board designed to create a strong forum for some types of User-Project discussion. But overall CNCF will lean towards "voluntary" and not "mandatory" requirements.
If you check out the PDF that fons posted above, http://rp.delaat.net/2015-2016/p50/report.pdf, then you will see pretty extensive testing showing that Weave Net, flannel, and Docker Networking have similar VXLAN performance for unencrypted traffic. In all cases, it is good enough. Alas the testers were unable to get Calico working.
The question is: when do you want top performance for encrypted traffic? Most of users want encryption for the wide area or public cloud, and when they can't use a VPC. Our solution is pretty good for these cases. Obviously at some point we'll enable IPSEC too.
Weave aims to deliver a completely portable network. In other words if you create an application using Docker container and a Weave network, that should be able to run anywhere. And all this should be 'magically simple'. Once you have decided where to run your app, you may wish to trade portability for performance gains. For example by using GCE networking (or Azure, or ...).
To date Weave achieved portability by sending some packets (inter host) through user space. This has big benefits in terms of ease of use eg. dealing with wide area networks, multicast and firewalls. But under load it performs worse than kernel-only models.
We now have Weave "fast data path" - http://blog.weave.works/2015/06/12/weave-fast-datapath/ ... This aims to deliver close to line performance with portability and extreme ease of use.
There may of course be yet more optimisations that end users wish to investigate. If you are willing to sacrifice some portability you could certainly make use of fast networks provided by a specific public cloud. We haven't yet seen a strong need to support this, but it is certainly a reasonable thing.
(Disclaimer: I work at Weaveworks)