I would add by a psychologist with admitted important lacks of knowledge:
From the paper abstract:
>Lack of knowledge on how the law was introduced, the degree of enforcement by the police, and behavioral changes in response to the law makes it difficult to attribute the lack of effect on bicycle crashes.
I didn't see quoted any stats about the wearing of hi-vis clothing. Just the assumption that legislation would lead to increased use.
The study was done by a psychologist. Maybe that explains it.