robots.txt use

Hi Kriesi

I am looking into the correct way to use my robots.txt with the awesome Enfold theme.
When i look at your robots.txt – http://kriesi.at/robots.txt

it shows:

User-agent: *
Disallow: /wp-admin/
Allow: /wp-admin/admin-ajax.php

Sitemap: http://kriesi.at/sitemap.xml

Is it fine if i do the same with my robots.txt obviously changing the sitemap url.

When i read the post Yoast wrote (Yoast article on robots.txt

he states:

We also do not block our /wp-admin/ folder. The reason is simple: if you block it, but link to it somewhere by chance, people will still be able to do a simple [inurl:wp-admin] query in Google and find your site. This type of query is the type of query malicious hackers love to do. If you don’t do anything, WordPress has (by my doing) a robots meta x-http header on the admin pages that prevents search engines from showing these pages in the search results, a much cleaner solution.

So why do you Disallow: /wp-admin/ ?

Thank you for your time