Wow. I don't know. With the way his upper body moved when he went down, it sure looked like someone had a fistful of jersey... Looked like it might have started innocently enough though, hand on the hip, to let him know he was there, then hand on the shoulder as he moved up. What do I know, but it kind of looks to me like Bos knew he was going down and decided to take the yellow jersey with him or maybe freaked out as he started to loose it and grabbed out of panic. Who knows. I hope he didn't do it on purpose.