Do you have a reference for that? I would be absolutely astonished if Google could be fooled into thinking that the two articles were completely different just by a couple of meta tags…
Yes you can post the same articles on many sites. It will increase your traffic.
Wrong!
Logically speaking, you can post on whatever you want and if more people click on things then you get more traffic. However, article directories are nothing but content farms and most of its traffic and PR probably comes from the same SEO spammers that advocate article publishing as a form of promotion.
Not only is it a terribly outdated practice, it gives you no benefit whatsoever and even if it did it’d likely be classed as duplicate content.