Comma, Comma, Comma Chameleon

When the old lion emerges from his den and roars, it behooves us to listen.

Here's William Gass in an essay about Elizabeth Bishop in the current edition (10/11) of Harper's:

"Alas, there are so many kinds of commas: those that lie like rocks in the path of a sentence, slowing its gait and requiring the reader's heed to avoid a stumble; their gentler cousins, impairing a pell-mell flow of meaning the way pebbles slow a stream; commas that indicate a pause for thinking things over; commas enclosing phrases the way the small pockets in a purse hug hairpins or collect bits of loose change; commas that return us to our last stop, and those that some schoolmarm has insisted should be placed, like a traffic cop, between 'stop' and 'and.' Not to mention those comma-like curvatures that function like overhead lighting—apostrophes they're called—that warn of a bad crack in a spelt word where some letters have disappeared to apparently no one's alarm; or claws that admit the words they enclose aren't theirs; or those that issue claims of ownership, called possessives by unmarried teachers. So many inky dabs—they enable José García Villa, in some of his wonderful comma poems, to write lines that ring like blows from a hammer:

And,lay,he,down,the,golden,father,
(Genesis',fist,all,gentle,now)
Between,the,Wall,of,China,and,
The,tiger,tree,(his,centuries,his,
Aerials,of,light)…"