The use case for our startup is: we have lots of compute and graphics intensive services being created and tested on Macs by developers, targeted for Linux Docker instances in the cloud. It would be nice to be able to run these same containers natively on OS X rather than requiring developers to bring up a local hypervisor (e.g. VirtualBox) and a local virtual Linux instance). This would help with both dev and test. Additionally, sometimes our engineers would like to be able to run compute jobs locally and merge the results back into the cloud based system.
That sounds like a difficult proposition without your target being able to run Mac binaries.
Having some sort of translation that's not a VM as a part of the distribution mechanism doesn't make much sense, and breaking the portability of Docker comes at a significant cost.
I think you're interpreting his words too literally. Nothing that gets deployed to a QA/staging/production system should be built on a developer's workstation in the first place, those specific containers need to come off a build server. The binaries on the developer's workstation would be built on/for OS X, and the binaries in QA/staging/production on the (Linux) build server for (Linux) targets.
