That is a guess. No doubt speed contributed .. which is just about everywhere for sure. Accidents happen very fast so .. I am not a Tiger fan (wasn’t he kinda a asshole) but there can be no doubt he is very much a household name.For the two previous days, he had been shooting videos for Golf TV, in addition to being in enough pain that he couldn't actually play in the tournament. Video and film shoots can be very long working days. If he was on a busy schedule and in discomfort, I can see him not adjusting well to another early morning wake-up call.