the question is what are they advertising... if it's lessons, then perhaps your' right.
also the Doctor said, it could have been mirrored image, or perhaps him just rotating the bar half way after a roll (although unlikely due to the line angles)... or perhaps he just rigged it like that in rush (as i did couple times

only noticing on the water, and not being bothered to re-rig).
Given that the bar/kite is designed to travel be-directionally, i wander if there is any difference how you actually rig it up...