A billboard message needs to be clear and focused and it just seems to vague. It's trying to make a claim without really saying anything concrete - almost the definition of a smear campaign.
If you had to make a billboard what would yours say? Its hard to fit in the reasons why 1914 is absurd, or blood transfusions are anti-biblical. It needs to be short, big lettered, provocative and intriguing. This makes it difficult to be so concrete, hence the website link, which I agree should not have a hyphen and be more memorable.