At present there is no way to skip the schemaref build for DS docs, and so there's a dependency on the DS server to build docs locally. This works fine, but can be more than you want to download daily just to test whether your small patch to the docs looks good in HTML.
It would be nice to have a flag to skip the schemaref for local builds.
For extra credit, in addition to documenting this, it would be nice to be able to install the Maven artifact for the sources (the ones you have changed) without running the install goal for the whole project. That might be just a Maven command.