Many of the subjects are just touched upon, whereas O´Connor really goes into them.
Yes , he spends pages telling you about all kinds of things you shouldn't do and after about 5 pages you get to the schematic that really works well. I don't find that an approach I like.
I have 5 of his books and they were really informative for me but I must say Merlin Blencowe's books are much better for me. A more practical way of dealing with amp designs.
I built a detuned cabinet for a 12 inch Electrovoice speaker and I like it very much but it's too big to get out of my attic.
Kevin's book Principles of Tone I consider worthless for my purposes and can't recommend it.
And what I find missing in his first books is a layout for his ampdesigns.
I used his London Power standard preamp and like it but because of the missing layout the distortion channel in my build is not good because it suffers from oscillation and I don't want to take the amp apart
as the clean channel is very good and totally quiet.