What a joy this was to read, from the standpoint of a textual bibliographer, a student of Chaucer, and a lifelong fan of Tolkien. While there was indeed plenty of food for the textb in me, I don't think it would be overwhelming for readers who might only be interested in how Tolkien's work on the Clarendon Chaucer (never published, materials recently discovered in 2012 - including groundbreaking discoveries with which he was never credited) influenced his fictional tales (as well as his other scholarly work, if one is, as I am, interested in those, too).
I found certain details of particular interest: Tolkien's distrust of fifteenth-century scribes (authentic spellings lost to their corruption), his overwhelming focus on details/accuracy ("counsels of perfection" are not good with deadlines approaching, which were never met not only on this project but others - especially when some of this is subjective work using what is/was available - his obsession with lost work caused him no end of difficulty - and we must remember that there was no standard ME dictionary at the time, so T's own A Middle English Vocabulary, his first book, was, again, HIS work), his sanitization of certain tales, his composition process, his complicated 'relationship' with the Skeat Chaucer (which feels rather personal), connections between specific CTs and Middle Earth tales, and the advocacy of the sons of both Tolkien and Chaucer (Chaucer's more speculatively, of course) on behalf of their fathers' work.
Ultimately, as Bowers notes, "unable as a philologist to give full voice to the lost past in deeds as well as words, Tolkien would seek this recovery in his fantasy writings" (lucky for us that he did) and "if readers have not previously detected Troilus and The Canterbury Tales in Tolkien's Middle Earth, it is because nobody was alert for noticing these ingredients." With the CC materials at hand, Bowers has done this for us, in entertaining as well as informative fashion.