Is there any reason not to use one of those false top tube clampy jobs when fitting a bike to a rack that clamps by the top tube?
My missus has a step-through bike and I could mount it upside down, but it'd be a faff. The rack manufacturer recommends using one of the clampy jobs, so I can't see any reason why not.
Any horror stories? Presumably as long as it's cinched up tightly around the headtube/bars and seattube, and they're both tight, it should be fine?