$form_state['input'] vs $form_state['values'] usage breaks default values

Sure, no problem. As it is right now, there is an assumption that 'input' will have some kind of data for the field. However, with most elements, you expect that, should a field not have any data submitted, then the '#default_value' attribute will take over

This is a more general issue with lots of the date elements, not just the code that I mentioned in my initial post.
Here is an example module. I attached it as a tar as well.

If you view the form normally and submit, then there is no problem and the default value is respected, but when, for some reason or another, there are no submitted values, as with the programmatically submitted form, the value for date is NULL, instead of the default value.

As an example where this comes up, without the need for programmatic submission, try settings '#disabled' => TRUE on the date_text field. Input boxes with the disabled attribute are no submitted by the browser, so when you disable the date box, it's value shows up as NULL even though it had a default value.

/**                                                                                 
 * Implements hook_menu().                                                          
 */                                                                                 
function l_menu() {                                                                 
  return array(                                                                     
    'l' => array(                                                                   
      'type' => MENU_CALLBACK,                                                      
      'page callback' => 'drupal_get_form',                                         
      'page arguments' => array('l_form'),                                          
      'access callback' => TRUE,                                                    
    ),                                                                              
    'l-date-sub' => array(                                                          
      'type' => MENU_CALLBACK,                                                      
      'page callback' => 'l_date_sub_page',                                         
      'access callback' => TRUE,                                                    
    ),                                                                              
  );                                                                                
}                                                                                   
                                                                                    
/**                                                                                 
 * Page callback to run a programmatic submit.                                      
 */                                                                                 
function l_date_sub_page() {                                                        
  $form_state = array(                                                              
    'values' => array(),                                                            
  );                                                                                
                                                                                    
  drupal_form_submit('l_form', $form_state);                                        
                                                                                    
  return 'page content';                                                            
}                                                                                   
                                                                                    
/**                                                                                 
 * Basic form function to test date element.                                        
 */                                                                                 
function l_form($form, &$form_state) {                                              
                                                                                    
  $form['date'] = array(                                                            
    '#type' => 'date_text',                                                         
    '#title' => t('Date'),                                                          
    '#default_value' => '2011-11-08 09:01',                                         
  );                                                                                
                                                                                    
                                                                                    
  $form['submit'] = array(                                                          
    '#type' => 'submit',                                                            
    '#value' => 'Submit',                                                           
  );                                                                                
  return $form;                                                                     
}                                                                                   
                                                                                    
                                                                                    
/**                                                                                 
 * Submit function to demonstrate value of the 'date' field.                        
 */                                                                                 
function l_form_submit($form, &$form_state) {                                       
  dsm($form_state['values']);                                                       
}