What a disappointment. This is strictly a book about J R R Tolkien’s own verse and very little about Old Norse writings and legends. To be fair, the book promises no more, but the result is unsatisfactory even on its own terms.

Two lays that J R R Tokien wrote in Modern English, one based on Völsung and the other on Guðrún, consume about half the book. There are also three short pieces, two in Old English. All use the alliterative Norse verse format. They are mildly interesting if you want to see how alliterative verse works in modern English, but even J R R Tolkien evidently did not think them worth publishing.

This is a typical stanza from Völsungakviða en nýa (my bolding).

Wild and witless - words of Signý,
that pain and torment - plead for kindred!
Glad will I grant it, - grimly bind them
in the forest fettered, - faint and hungry.

--J R R Tolkien: The Legend of Sigurd and Guðrún, Christopher Tolkien (2009)

The remainder of the book contains commentary by Christopher Tolkien, J R R Tolkien’s son, on his father’s verse and opinions. It could have been interesting but unfortunately the quality of the writing is so poor that much of it is barely intelligible.