Thanks for this. I thought I had deactivated it, but I didn't.
It's worth noting that the mobile theme doesn't appear to be compatible with the ComicPress Theme - which is a big theme heavily used by makers of webcomics.
By not-compatible, what I mean is this: your comic disappears on mobile devices. Not that the whole site breaks down.
But, when the whole point of your WordPress site is the comic and not the words, that's a pretty big failure. So I think it's fair to say that Jetpack mobile is totally incompatible with ComicPress.
My site hasn't worked on mobile devices for days now, till I found this, which is a real bummer. Seems okay now once I deactivated.