One of the limitations of using a standard A/B split test is that it won’t work out of the box if the page you are testing is the “action” page for a form that uses method=POST.
For example, lets say you have a simple form page – form.html that looks something like this:
You’ve created process_form_2.php to split test against process_form_1.php.
The problem is that when process_form_1.php redirects to process_form_2.php, you will have lost all of your form data since your form uses POST.
There are two solutions for this:
1. Switch from method=POST to method=GET.
If this is an option, it’s probably the easiest solution.
2. Setup the experiment as a multivariate experiment and change the form action line in the HTML.