When I started trying to write poetry in traditional forms, I was often praised with something like "That's so cool! I didn't even notice it rhymed until I reread it!" And then, as suspicions were confirmed by counting the lines, "Hey, it's a sonnet!" I was an idiot and I was pleased. That led to monstrosities like this piece:   
 
Broken Pastoral
 
 
 
Fred, who dug our well, lived on the hill 
Out back. He kept his banty roosters chained 
To keep them from each other's bellies. Still 
They screamed all night and day unless it rained. 
He married Carolyn just to get the land, 
Then kicked her out for Peaches. Everyone 
Except for Carolyn knew it's what he'd planned. 
When she'd drive by, he'd get out his gun. 
Of course, we didn't know. My wife had kin 
Nearby, but only James would stop to talk 
And he was Carolyn's brother.  He'd bring 
His photographs to show us, folks who'd been 
To college.  After we hired Fred, he'd walk 
By less. We moved away before the spring.
 
 
Iambic pentameter is fragile: we hear singles, doubles, triples, and  even quadruples pretty well, but quintuples push the limits of our attention. How many tunes in 5/4 time besides Paul Desmond's "Take Five" can you name? Can you count that one some other way than "1 2 3 - 1 2" and still get the accents right?  In the thing above, the relentless enjambments and the full stops near the beginnings and endings of lines make it impossible for even me to hear a pentameter. It just isn't there, despite the fact that foot by foot there are only four substitutions and three of those are "x CAR / olyn X."
 
Perhaps it's true that many people, even educated people, even people who can scan a little, no longer know how to read or hear pentameter. I've cited before the evidence that Charles Bernstein, Helen Vendler, and Ron Silliman have trouble with it, but so does anyone who will tell you that prose or natural speech sometimes approximates anything as highly wrought as IP. It goes the other way — in skilled hands, IP can play across natural speech to produce rhythmic effects otherwise impossible in English. Here's Robert Frost, with a single sentence, as many metrical substitutions as I used above, and not much more end-line punctuation, making absolute magic: 
 
The Silken Tent
 
 
 
She is as in a field a silken tent 
At midday when the sunny summer breeze 
Has dried the dew and all its ropes relent, 
So that in guys it gently sways at ease, 
And its supporting central cedar pole, 
That is its pinnacle to heavenward 
And signifies the sureness of the soul, 
Seems to owe naught to any single cord, 
But strictly held by none, is loosely bound 
By countless silken ties of love and thought 
To everything on earth the compass round, 
And only by one's going slightly taut 
In the capriciousness of summer air 
Is of the slightest bondage made aware.
  
      8:27:55 PM       
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