They suck at high speedsI donno... there's a video of a woman riding a big cruiser motorcycle with ape hanger handlebars maneuvering through an advanced riders skills course,
weaving around cones,
doing figure eights and U-turns, in a parking lot. She does it well.
Once you get used to unusually high handlebars, it seems to me you can make them work to get the bike to do what you need it to do.