Hey Sommer,
You can achieve that by custom javascript coding, where we can show or hide progressive profiling fields in a progressive manner( that is on the first visit we have the normal fields showing, and the progressive profiling fields are hidden, and on the second run the progressive fields will show up with some fields of the first run hidden and email field (specifically) will show( but disabled to edit the email) and below the email field we will append a text link: 'not you', which upon click will clear out all the old values and redirect to a fresh page URL( the old cookie will be deleted for known users).
What basically happening is that based on the prefilled email field value we are showing fields in a progressive manner.
Hi Sommer,
I worked on very similar requirement just 2 days back. Initially, I also tried to use Forms 2.0 functionality of 'Known leads'. Forms 2.0 editor allows us to select to show either 'the form' or 'custom html' if the lead is 'Known'. When we select 'custom html', the 'form' is not included at all in the html generated. That's what I found in my testing.
If we choose 'show custom html', we can write custom javascript there. It is easier to do things like 'redirect' to another page etc there. But what I found that since the 'form' is not included (we chose to include custom html instead), we can not manipulate the form object in that custom html.
We can add form ourselves and manipulate the fields using Forms 2.0 API javascript though.
For my particular business need, I also ended up not using 'Marketo forms 2.0 Known leads' custom html. Instead I used custom javascript to render the form differently based on the prefilled email field as Alok said above.
I think in your case also, you might have to determine 'known' leads based on email address / or cookie yourself in javascript and manipulate progressive fields based on that.
Rajesh