You guys have a really awesome product, good work! I think I misinterpreted your question as "How do you prevent the form API from being used to send unwanted

You guys have a really awesome product, good work! I think I misinterpreted your question as "How do you prevent the form API from being used to send unwanted email", not email filtering. We also apply a spam filter to outgoing email requests, but as you stated, it's a challenge to balance that with usability. Thanks for your feedback!