Donald and Emily Egan took a bike tour with Vermont Bicycle Touring

(VBT) of Virginia's horse and wine country. VBT planned the route, rented the bikes, supplied tour guides, and provided a van for people who wanted to ride in it for part of the tour. They warned riders that traffic on part of the ride might be heavy and that the shoulder was narrow, and they could opt to ride in the van. After the Egans had ridden almost a mile on the part warned about, they were hit by a driver, Jenkins, who was legally blind, incompetent, and whose license had been confiscated by his guardian. Donald died and Emily was seriously injured. VBT defended against the Egans' negligence suit by arguing that it was not the proximate cause of the accident. Was Jenkins a sufficient superseding cause of the injuries so that VBT should be held not to be the proximate cause of the injuries?