Linux no-reboot patching can be a mixed blessing.
The startup scripts and their configuration are another "thing" to be managed. If you are undiciplined, and start up services by hand, on a reboot you end up with a non-functioning platform. Backing out the patch won't help, because it is the manual service starting (and possible fiddling) that is not tested.
So even if you no-reboot patch you must still schedule down time for a reboot - when you are ready to handle the potential non-availability of the server - in order to test the start-up process.