What is the advantage of using header-catname.php over is_category(‘catname’);?

Let’s say I have a category named as catname (the slug would be catname). I want the header styled differently when visitors open the category catname.

The article on Ghacks explains how to create a custom header (styled differently) when visitors open the category catname, achieved by creating header-catname.php and including it in category-catname.php with include(TEMPLATEPATH.'/header-catname.php'); (instead of the usual get_header(); ). You can read the short article itself if my explanations is difficult to follow (I apologize for my lack of proficient English).

My question is: what is the advantage of using above method, over using is_category ('catname') in header.php to create custom header only for the catname category?

I mean, in the header.php we could just use this without creating additional header-catname.php:

 <?php if ( is_category('catname') ) { ?>

 /* Insert custom header for category catname here */

 <?php } else { ?>

 /* Insert the usual header here */

 <?php } ?>

Does using the conditional IF make the page load slower? Or is there any disadvantage?

The article on Ghacks is actually a pretty silly way to do it as well.

The get_header() function is actually a pretty smart function. You can do some neat things with it. For example, you can do this:

get_header('category');

That will cause it to load the header-category.php file, if such a file exists, or the header.php file, if header-category.php does not exist.

Here’s a cool way to make use of that property:

if (is_category()) {
  $cat = get_queried_object();
  get_header($cat->name);
}

This will cause it to load header-catname.php, using the actual category name, with a fallback to header.php if such a file does not exist.

If you want, you can even extend that to be more generic and work for any taxonomy:

if ( is_category() || is_tag() || is_tax() ) {
  $term = get_queried_object();
  get_header($term->name);
}

Lots of neat things you can do with those template fallbacks.