title: Is this responsible and defensive, or paranoid and obsessive?
body: <p>Sometimes there's a fine line between being safe and running scared.</p>
  
  <p>Does this code cross the line into scaredy-cat zone?</p>
  
  <pre><code>DuckbillPlatypusForm dbpf = null;
  if (radioButtonUseExistingPlatypus.Checked) {
      dbpf = new DuckbillPlatypusForm(DuckbillSetupUtils.DuckbillPlatypusState.Readonly, funnyMammalIDs);
  } else if (radioButtonCreateNewFromExistingPlatypus.Checked) {
      dbpf = new DuckbillPlatypusForm(DuckbillSetupUtils.DuckbillPlatypusState.Template, funnyMammalIDs);
  } else if (radioButtonCreateNewPlatypus.Checked) {
      dbpf = new DuckbillPlatypusForm(DuckbillSetupUtils.DuckbillPlatypusState.StartNew, funnyMammalIDs);
  }
  if (null != dbpf)
  {
      dbpf.Show();
  }
  </code></pre>
  
  <p>After all, there are only three radio buttons, and one is checked at design time, so dbpf can never be null, right? Unless somehow all of the radio buttons become unchecked at design-time, or I add another radio button without updating this code, and that one gets selected, but at what point do I just "bite the bullet" and accept suchlike risks?</p>