Re-enabling Submit after prevent default

Don't try to set up and cancel a submit handler from within your validation function, do it the other way around: call the validation from within a single submit handler, and only call .preventDefault() if the validation fails:

$(document).ready(function() {

    $('#ShoutTweet').submit(function(e) {
       if (/* do validations here, and if any of them fail... */) {
          e.preventDefault();
       }
    });

});

If all of your validations pass just don't call e.preventDefault() and the submit event will then happen by default.

Alternatively you can return false from your submit handler to prevent the default:

    $('#ShoutTweet').submit(function(e) {
       if (!someValidation())
          return false;

       if (!secondValidation())
          return false;

       if (someTestVariable != "somevalue")
          return false;

       // etc.
    });

I'm not completely sure what you are asking, but if your goal is to destroy your custom submit handler, then use this:

$("#ShoutTweet").unbind("submit");

This assumes that you have a normal (not Ajax) form.