Visual Studio Team System - Magic Tests

I've been playing around with the unit testing in VSTS and I really like what I see.  For example, it fully supports building tests that will drive the user interface of a Windows Forms application by calling the various Form event handlers. 

For example, if you have a Button1_Click in a form, you can generate a test for it that looks like:

    [TestMethod()]
    public void button1_ClickTest()
    {
        Form1 target = new Form1();

        TestProject1.WindowsApplication1_Form1Accessor accessor = 
            new TestProject1.WindowsApplication1_Form1Accessor(target);

        object sender = null; // TODO: Initialize to an appropriate value

        EventArgs e = null; // TODO: Initialize to an appropriate value

        accessor.button1_Click(sender, e);

        Assert.AreEqual(accessor.label1.Text,"This is a test");
    }

Look at what's going on here.  The test doesn't call into Form1 directly.  It wouldn't be able to, as button1_Click is private.  Instead, it creates an instance of a proxy class called "accessor".  This is some code-generated goo that uses reflection to get at the private members of the form.  This also lets you do stuff like "accessor.label1.Text", which is also private.  This part is ½ magic.

The full FM is this; the windows form application that I'm testing compiles to an EXE, not a DLL.  How is my unit test (which is in a separate assembly) able to call into a function that's inside of an EXE?  And, does this open the door to something similar to OLE automation of applications?  Inquiring minds want to know.