Some stanzas need negate option to override

Also if https://bugs.launchpad.net/upstart/+bug/282854 is ever implemented, a way to negate those should be available.

Agreed, this is needed to make the override files really useful.

I've just run into a case where being unable to negate respawn in an override file is definitely limiting. For example, I'm using an automated provisioning environment (Puppet, as it happens, but applies to Chef or any other such system). The main /etc/init/job.conf file is the "production" job configuration. The provisioner may lay down /etc/init/job.override to change job settings for the "development" environment. In our case, we need to negate respawn as the development-mode for the job runs the service via a watchdog with reload-on-changes (node.js' supervisor module). If anything goes wrong with the service, supervisor's restart limit and upstart's respawn tend to interact badly, causing a job that perpetually fails. Yes, I can mess with respawn limit, but that's not a truly robust solution.

I've found others have run into similar difficulties with overrides from a lack of a "norespawn" style stanza, e.g. http://oss.clusterlabs.org/pipermail/pacemaker/2012-February/013324.html