I have used the: interceptAction("SubmitAction", "around", func) action
to catch the click of the submit button, and if bad things happen,
redirect them to a URL.

And I know that to let the Submit continue, I can in my else case:

var result = invocation.proceed();
return result;

But what if I want them to hit Submit, test, if bad, redirect. If good,
let the submit happen, then redirect after the submit?

Can I do that? Seems like when I return invocation.proceed() that I am
done, aren't I? And my opportunity to do something else is over? If I
redirect before, does the Submit happen?