That's true enough. Modern lyric poetry, with its symbols and metaphors, its arcane allusions and teasing line breaks, is fairly bad at giving us the facts. We no longer live in an age in which the skills of beekeeping, say, are explained by the greatest verse-maker in the language, as Virgil does in The Georgics. Even those jolly mnemonics about the weather or the Greek alphabet are fading from consciousness. It's a pity, as I often think I might get the gist of assembling a new piece of flatpack furniture quicker if the instructions were wittily rhymed.
So why translate? My first answer is that poetry in translation simply adds to the sum total of human pleasure obtainable through a single language. It opens up new language worlds within our own tongues, as every good poem does. It revitalises our daily, cliche-haunted vocabulary. It disturbs our assumptions, jolts us with rhythms flatter or stronger than we're used to. It extends us in the way real travelling does, giving us new sounds, sights and smells. Every unique poetry village sharpens us to life.
Some people would disagree, saying poetry in translation is the wrong side of the tapestry - it just can't be done. But they are talking about replication, not translation. It is perfectly true that you will never get a replica of the original - nor would you wish to. The way it works, when translator and original are in tune, is that a third poem is created. It is the child of two parents and simply couldn't exist without them.
How poor modern Anglophone poetry would be without Edwin Morgan's Mayakovsky, Anne Carson's Sappho or Mark Musa's Dante; without George Szirtes's Hungarian poets or Ian and Jarmila Milner's Czechs. What a loss to the itinerary if we didn't have the journal Modern Poetry in Translation to transport our imaginations across the globe in 80 seconds.
Translation practice currently is a broad church, including what is a heresy to some - imitation. Some translators foreground their own reaction, and use the original as raw material only. Others live with a single poet for years in order to find a way of reflecting every nuance as truthfully as possible. As long as the translator is completely honest about the way in which he or she is using the original text, this is all to the good. One poem may generate all kinds of word villages.
For poets themselves, reading work in translation is an immense stimulus. It may be the means by which they find themselves. Would we have had the uniquely Keatsian Ode on a Grecian Urn if Keats had never looked into Chapman's Homer?
James Buchan's claim that readers who like The Whitsun Weddings won't like Schneepart is wide of the mark. It implies you can't admire utterly different poets (you can, and all real poetry lovers do). Besides, under Philip Larkin's lucidity and Celan's obscurity, lie two not dissimilar imaginations, both concerned with death. Larkin even has the occasional Celan-like compound-word - "almost-instinct", for example.
Buchan quotes a Celan poem he finds "extremely beautiful" - which partly answers his own question. Celan's poems are often beautiful, sometimes ugly: sometimes they pierce us like icicles. This one was translated by Michael Hamburger:
You were my death:
you I could hold
when all fell away from me.
That icicle of consolation is surely from a village not far from Larkin's?