Originally Posted by GregorRichards
It "seems" to work, in that it appears to shut down my DR800SG and doesn't leave it in some horrible unbootable state.
Using the original simple script I did, it was 92% when I did the shutdown, and 18 hours later when I booted it back up it was still at 92%. So that's good news. Your version is a lot safer than the script I had, but the results should be similar.
I'm going to keep going down the path of putting it into sysd though, mostly just for the fun of doing it.