How Split-Testing Our Opt-In Form Increased Our Conversion Rate by 102.2% 15 years ago
Agreed. I feel the majority of the science behind this is simply keep things clean and minimal. I would hypothesise 'Get Email Updates' would do better than 'Get Free Email Updates', too.
I don't believe a statistic offers any significant social proof. Lots of faceless people i don't know have signed up. So what?