clouds.yaml file documentation is misleading

[Chris]

The cloud.yaml.template at https://github.com/openstack/horizon/blob/master/openstack_dashboard/dashboards/project/api_access/templates/api_access/clouds.yaml.template
states that if I only have one cloud I don't need to set OS_CLOUD or --os_cloud=...
I found this to be incorrect. I needed to set OS_CLOUD even with a single cloud listed in ~/.config/openstack/clouds.yaml. Its possible I'm using it wrong. Its possible I'm using an outdated client, but I wasted 30minutes banging my head against this and it would be nice if we could save someone else the same wasted 30 minutes.