I'm not sure I understand your use case... If you already have a contact's details beside their email address, why would you need to pass those again through a landing page form?
The idea behind a Blind Form Submit is that someone can submit a predefined response. You can use it for example to confirm double opt-in, measure interest for a particular subject compared to others and so on. It only works in emails however, because the required connection to the contact's email address is already established there.