"[2] Critics note that Tolkien attempted and sometimes failed to follow the rules he laid down in the essay in his own alliterative verse, in his own translations, and indeed in the poetry in his narrative fiction such as The Lord of the Rings.

The essay is divided into the following sections (which are arranged hierarchically but not numbered in the original): Tolkien comments on the risk of using a translation as a substitute for study with grammar and dictionary, calling it an abuse, and writing that On the strength of a nodding acquaintance of this sort (it may be supposed), one famous critic informed his public that Beowulf was 'only small beer'.

[10] Tolkien mocks "oddities" like "ten timorous trothbreakers together" (for Beowulf line 2846, in Clark Hall's unrevised version) as "reminiscent of the 'two tired toads that tried to trot to Tutbury'".

[11][b] He does not approve, either, of choosing needlessly colloquial words: "Too often notables, visitors and subalterns appeared instead of the more fitting, and indeed more literally accurate, counsellors, strangers, and young knights.

[13] But on the other hand, he criticises William Morris for using the dead and unintelligible 'leeds' for OE leode ('freemen', 'people'; cf German leute), even if antiquarians feel that the word ought to have survived.

Some terms present special problems; the Beowulf poet uses at least ten synonyms for the word 'man', from wer (as in werewolf, a man-wolf) and beorn to leod and mann; Tolkien writes that in heroic verse there were over 25 terms that could at a stretch be used to mean 'man', including words like eorl (a nobleman, like 'earl'); cniht (a young man, like 'knight'); ðegn (a servant, like 'thain'); or wiga (a warrior).

In the case of compound words, Tolkien observes that the translator has to hesitate between simply naming the thing denoted (so 'harp' 1065, for gomen-wudu 'play-wood'), and resolving the combination into a phrase.

Whereas, he argues, the Old English word hlaford, meaning 'lord' (which derives from it) was all that was left of the antique hlafweard ('loaf-guard'; the word originally meant 'bread-keeper') in daily speech, the poetic phrases used in verse retained echoes of another world: He who in those days said and who heard flæschama 'flesh-raiment', ban-hus 'bone-house', hreðer-loca 'heart-prison', thought of the soul shut in the body, as the frail body itself is trammelled in armour, or as a bird in a narrow cage, or steam pent in a cauldron.

The poet who spoke these words saw in his thought the brave men of old walking under the vault of heaven upon the island earth [middangeard] beleaguered by the Shoreless Seas [garsecg] and the outer darkness, enduring with stern courage the brief days of life [læne lif], until the hour of fate [metodsceaft] when all things should perish, leoht and lif samod.

And therein lies the unrecapturable magic of ancient English verse for those who have ears to hear: profound feeling, and poignant vision, filled with the beauty and mortality of the world, are aroused by brief phrases, light touches, short words resounding like harp-strings sharply plucked.

Tolkien states that "The main metrical function of alliteration is to link the two separate and balanced patterns together into a complete line",[20] so it has to be as early in the second half-line as possible.

"[21] His version of this captures the rhyme and the alliteration, as well as the meaning: Tolkien ends the essay with an analysis of lines 210–228 of Beowulf, providing the original text, marked up with stresses and his metrical patterns for each half-line, as well as a literal translation with poetical words underlined.

This is seen, he argues, not just in such small details, but in the parallel arrangement of narrative, descriptive and speech passages; in the use of separate passages describing incidents of strife between Swedes and Geats; and at the largest scale, in the fact that the whole poem itself is like a line of its own verse written large, a balance of two great blocks, A + B; or like two of its parallel sentences with a single subject but no expressed conjunction.

Hall further comments that in 'Lays of Beleriand', Tolkien failed to heed his own warning against archaism, as he uses the word "weird" archaically to mean 'fate' (OE 'wyrd'), and speculates that this may have been a reaction against the "rigidity and formality of translating authentic Anglo-Saxon literature.

"[23] The Green Man Review comments that Tolkien's "emphasis as a translator was on selecting the word that best fit the tone of the poem.

She recalls her own Beowulf studies with "a huge stack of dictionary and grammar books", and draws attention to Tolkien's comment that "Perhaps the most important function of any translation used by a student is to provide not a model for imitation, but an exercise for correction.

"[12] Magennis argues that This conviction provides the rationale for an elevated register incorporating archaizing features, such as he finds in Wrenn's 'Clark Hall': 'If you wish to translate, not rewrite Beowulf', declares Tolkien, 'your language must be literary and traditional: not because it is now a long while since the poem was made, or because it speaks of things that have since become ancient; but because the diction of Beowulf was poetical, archaic, artificial (if you will), in the day that the poem was made.'

[12]The scholar Philip Mitchell comments that "The entire essay is worth serious study" and notes that among other points made by Tolkien, "Anglo-Saxon verse is not attempting to offer puzzles but an aesthetic of compression in a slow meter of balance.