I have an ongoing issue with our forms.
I send an email to Jenni Smith at company a.
Jenni then forwards the original email with to a colleague, Josh Smith.
Jenni the clicks link in email, goes to web registration page and completes the web registration form.
Josh clicks on the link in the email from Jenni but sees that Jenni's first name, last name etc are cookied in the form. He does not change the first name or last name but answers the additional progressive profile fields.
Jenni shows as registered but then her data is overwritten, first and last name, to Josh Smith.
I read that there is a token you can use {{form.not you}} to prevent this from occurring. Has anyone used this token? Or are there other suggestions besides field block to prevent contact records from being overwritten?
To be precise, if the link click is Josh's first visit to the page in his browser, Jenni's data is not "cookied": you don't even need cookies (Munchkin) enabled for this to work. It's actually using the mkt_tok -- the "instant associator" query param -- to fetch the prefill fields. The effect is akin to having an existing associated session (mostly), but I want to be precise.
But there's something amiss in your description. If Josh "does not change the first name or last name" then Marketo is not going to magically know his name is Josh Smith. Did you mean to say, "only changes the first name and last name"?
This has less to do with progressive forms and more to do with the prefill on the form and the tracking token.
You can certainly add a Not You to clear out the form, but this is rarely done.
I believe Sanford has some options for fixing this, but it's been a known problem for years and there are alot of threads on it.