There has been some confusion on the way Wiebel changes tack. This may have been caused by the video, in which it is stated that Wiebel can tack. It would have been better to state that Wiebel can change tack.
For the record, Wiebel jibes. Wiebel jibes pretty much the same way as a windsurfer does, with the additional feature that the mastfoot moves from left to right or vice versa along the curved rail at the front of the frame during the jibe.
Regards,
Walter Hart