> So how is this applicable in nvidia-kernel-common where there is no > daemon to stop and calling the script with stop does nothing? > > It saves the effort of calling the script if it does nothing.
I can see in /etc/init.d/rc that "# Debian Policy ยง9.3.1 requires .sh scripts in runlevel S to be sourced". So runlevel 1 corresponds to runlevel S in Debian et derivatives (stop me and shout if this is not the case!) So, the file is normally source, but we can also avoid to do that for nothing.