Today, nested AbstractBranchAwareProject's try to schedule themselves onto the same node and share a workspace, if their workspace has been deemed immutable.

My current attempt at this was to implement "getSameNodeConstraint":
https://github.com/jenkinsci/yaml-project-plugin/blob/master/src/main/java/com/google/jenkins/plugins/delegate/AbstractBranchAwareProject.java#L230

However, this doesn't appear to work as I had thought. So instead we should consider doing something with: http://javadoc.jenkins-ci.org/hudson/model/labels/LabelAssignmentAction.html