Hey, if it works for you great! Problem solved. If you run into problems, I
would focus on udev. GNU/Linux switched to that years ago for a reason. I
try not to create hacks just to create hacks. I create hacks if I don't have
a better solution available. Use udev.
If you nevertheless still want to fool around with things at this level,
maybe you should look at the hdparm utility. It was installed on my system by
default. Just type: man hdparm
Apparently it can be used to control spinning down a disk.
Good luck!
