Is Googles Duplicate Content Penalty a Myth?

I havent understand what are the things you want to know..can you elobrate.

@Abhishek,
I also have not followed your question.Is it something related to finding out which is the original content?.

It is the possibility of Google identifying a second or a number of pages that are basically the same AS original content

Let me clarify.

It means that if you are posting duplicate contents resulting into same output then those replicated or duplicate contents or pages will not be indexed by Google and you may have to face a penalty for this.

I hope now this explanation is enough..

Anybody experienced with it may answer this question, I hav not tried it yet.