I first read this as a student a few years ago, and loved it. It really opened up the doctrine of the Trinity for me and, as the book promises, some of its practical implications. And most of it is pretty great still, and achieves what it sets out to do.
However, I decided to re-read the book, in light of some changes to my understanding of the Trinity, resulting from last year's debate about the Trinity and the Eternal Submission of the Son. This found Wayne Grudem and Bruce Ware, among others, under fire for departing from the traditional understanding of the Trinity in order to provide an ultimate theological grounding for complimentarianism. In seeking to (rightly, in my view) defend a biblical understanding of male headship, these theologians were accused of introducing the unhistoric and unorthodox idea that the Son is eternally submissive to the Father, rather than submissive simply in his incarnation. I'll confess to having previously held this view myself, as an uncritical member of circles in which Grudem and Ware are well-respected; however, the helpful work of people like Carl Trueman, Liam Goligher, Fred Sanders, Mark Jones and others has helped me to see how anomalous the idea of eternal submission within the Trinity is.
Sadly, as I suspected when I decided to reread this, Allberry endorses this doctrine wholeheartedly in his chapters on gender and marriage. Unsurprisingly, he quotes regularly from Grudem and Ware. Amusingly, he quotes Fred Sanders a few times in earlier chapters, which is ironic given that Sanders comes down against ESS.
In spite of how helpful and accessible a lot of this book is, I couldn't now recommend it, given this heterodox understanding of the inner workings of the Trinity, even if it is deployed in the honourable cause of defending biblical gender roles.
I find it hard to hold it too strongly against Allberry - he's not a theologian proper, but a practical pastoral minister, clearly influenced strongly by conservative evangelical theological gatekeepers like Grudem and Ware, who bear more responsibility for avoiding these missteps.
And, please note, I write all of the above as a conservative evangelical myself, who probably comes down even more conservatively on gender roles than many of my peers. I'm hopeful that Allberry, and others like him within our tribe, can humbly adjust their understanding and teaching of Trinitarian doctrine to be more in line with the traditional and biblical understanding.