[sbarre]

So you're going to intercept and ask every single user who lands on your inbound signup page before you let them sign up?

That doesn't feel like a great user experience. As a user, I would just button past that pop-up or form.

The goal with these kinds of analytics is not to get referral information from only users who sign up, but for anyone who lands on the page - maybe just to read about you at first - so you have a sense of where they came from and how your marketing spend is doing.

Most paid traffic doesn't convert. If you want to know how much of it is converting, you need to also know how much didn't convert.