Personally, I liked John M Ford's ideas a heckuva lot better.
Which was?
'
The Final Reflection', written by John M Ford and, at the time, acclaimed as
THE book about Klingons. Very highly recommended. JMF also wrote the excellent 'Klingon' supplement for FASA's 'Star Trek' role-playing game, which borrowed extensively from his book.
TFR was written as a book-within-a-book, with Kirk and co at beginning and end reading about events that wound up forty-odd years before. Note also that this was written
before TNG and the Klingons being retconned into Space Bikers. It also extensively used the '
Star Trek Spaceflight Chronology' for background.
Anyhow, Ford's take on the Klingons was as follows. 'Imperial' Klingons are the ones with bony ridges, attitude problems, etc.. In the course of building up their Empire, they have become adept at genetics, and have used this on themselves. The main result has been the creation of 'Fusions' - Klingon sub-races (originally lab-created, but later breeding unassisted) incorporating some genes from certain foes, so that the Empire can fight or otherwise interact with said foes more effectively.
(Part of the reason, too, is that Imperials are fairly specific about their preferred environment. For them, the Human norm is rather chilly, Imperial Klingons like it unGhodly hot and unGhodly humid. Fusions are OK with whatever is standard for Klingons AND whatever race they got their other genes from.)
The most common Fusion type is Human (TOS Klingons). There are also a good number of Romulan Fusions. The RPG supplement had rumours of Fusions of other races (Vulcan, Orion, Andorian, etc.) but these are so rare as to be almost unheard of. Fusions tend to be assigned to border regions associated with their type - Human Fusions against the Federation, Romulan Fusions against the Romulans, etc..
Fusions consider themselves Klingon to the core, and prejudice against them is minimal. Imperial Klingons have a slight inside track on some things, but there is nothing stopping a sufficiently skilled / ruthless Fusion from rising to the top.
Can't really do it all justice here. There are also side-elements like 'The Black Fleet' and 'The Great Game' and the 'Komerex / Khesterex' debate and so on. It is a damn good book even if, like a lot of others, subsequent canon has pushed it aside.