That's a good way to look at it. I wasn't aware of the background of the song, only the finished product. It does sound a bit thrown together. It's not a bad song by any means, it just doesn't do much for me. It's over before you have a chance to dig it.
I like a lot of Black Sabbath, and there is also a lot of their stuff that I don't like. I've never really figured out what it is about any given song that grabs me or repels me. You're right in that this song doesn't have a common structure, possibly because it is so short; there's almost no room for it to even have a standard verse-chorus structure. The "Can you help me?" section is definitely the refrain, it's just not really long enough to call it a chorus in the traditional sense. I guess by "by the numbers" I just meant that it has a number of Black Sabbath trademarks, as you've mentioned, but in smaller doses. A riff, a melody, a dash a weirdness, stir and season to taste, instant Black Sabbath song.