

The Most Comma Mistakes - danso
http://opinionator.blogs.nytimes.com/2012/05/21/the-most-comma-mistakes/?hp

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sp332
_The syntactical situation I’m talking about is identifier-name. The basic
idea is that if the name (in the above example, “Jessie”) is the only thing in
the world described by the identifier (“my oldest friend”), use a comma before
the name (and after it as well, unless you’ve come to the end of the
sentence). If not, don’t use any commas._

I've never heard of this rule before.

