Rodney,

Metaphor-
A figure of speech in which a word or phrase that ordinarily designates one thing is used to designate another, thus making an implicit comparison.

you said:

"For a line to stand on it's own, it metaphorically is like a human being and possesses the same qualities if it is to stand out from the crowd of lame lines."

So what your saying is that to stand alone
does not do well for a song because it is not with the group.

That makes my brain hurt...

DAvid