[Yves S L]

I reckon extended rhymless iambic pentameter is harder than rhyming, as having to rhyme actually restricts the possibilities of things you can say, and, also, without the end-rhymes you have to work harder to make music. Once you have the shade/made rhyme, then if you have "birds" then there is only so many rhymes available, so if you choose birds/words then your theme is kinda set and you can just go on riffing. It is not like the themes and ideas and motifs are original to Auden. Take for example what Frost makes of the old chestnut that is the birds/words rhyme:

The bird would cease and be as other birds
But that he knows in singing not to sing.
The question that he frames in all but words
Is what to make of a diminished thing.

The poets bend their ideas around the rhymes.

If someone has the syntactic flexibility and sufficient control of rhythm to make extended rhymeless iambic pentameter interesting, then the person needs a few additional ingredients to be able to rhyme convincingly, ingredients that musicians who take interest in rhyme and meter tend to already possess in abudance. Can a person acquire the ingredients? Sure. Can someone else tell them a step by step recipe of how to acquire the ingredients? Well, it is an illusion that anything can really be taught, because at some point in the process a person has to think without anyone else's help.

Also, sometimes rhyme and meter is not supposed to be unobtrusive.

The challenge, though, is not rhyme and meter, but having something to say.