On a serious note, I have watch Kim take her 'bent down a rough potholed stony track and make it look easy. Quite a few upright riders were struggling a bit with the track, but Kim just stormed down it like it was smooth bitumen. I would never have believed a short wheelbase bent could go over rough roads until I saw that.
In my defence, I was just the right amount of stoned at the time
Seriously, there's an actually-it-is-about-the-bike factor there. For all its SWB recumbentness, the Streetmachine is extremely stable (I've even recovered it from front wheel skids, something I've never managed successfully on a mountain bike) and the relatively wide tyres and clever suspension allow you to roll over surfaces that most touring or even cross bikes would object to
[1]. That's kind of the point - it's a full-on expedition tourer, so is designed to handle unmade roads well. The sticking points are that the front wheel is small, so there's a limit to what you can roll over - most potholes are fine, but kerbs really aren't - and that you can't usefully get a foot down (and should you do need to it takes time) so if you attempt something silly you're pretty much committed. Its 20" rear wheeled relative, the Grasshopper is better suited to comedy off-roading for this reason.
While that sort of thing would be possible on other types of SWB 'bent (I recall descending a much more terrifying muddy bridleway with Johnny Thin of this parish on his Toxy lowracer), it would be a lot less pleasant, and with the twitchier handling of something like a Hurricane, a fair bit easier to cock up.
[1] This also gives it an edge over many faster recumbents for crazy descending.
