What if you don't want the Submit button to be below the form, ie - a single field with the Submit button to the right? Not being able to move the submit button out of it's row seems like an arbitrary and unnecessary limitation.
Glad to see there is a solution, but I'm sorry ... In what world is that intuitive or user friendly? This is just like renaming things in Marketo. There is no visual cue letting the user know it's anything more than a static element.