title: Magento adminhtml custom (customer) tab add fields correct
body: <p>I want to add a custom tab to the edit customer page.
  Now that is not a problem.
  But i wondered, is there a perfect way to add input fields in that tab?
  Because every tutorial uses a phtml file where you add code yourself.
  But is it possible to fill this tab programmatically?</p>
  
  <p>Thanks in advance!</p>