I'm pretty much done with the second book I've been reading, Peaceful Death, Joyful Rebirth, by a Tibetan lama. It's a very good companion piece to The Tibetan Book of the Dead, of which I've also just completed a reading.
For years, I had been reading The Tibetan Book of the Dead in a loop read – after completing it, I'd go back to the beginning and start over, usually after morning sitting. I stopped last year when I was in the throes of insomnia and that disrupted my morning sitting. This was the first full read-through since then.
I don't recommend either of these books generally. They should only be read by people who are ready for them. Back in the Bay Area, Nobuko, an Oberlin friend and former housemate, mentioned she had read it back in college or soon after, and she didn't get it, I think she said. The overall feeling I got from her about the work was not necessarily positive. She wasn't impressed, at least.
To me, I feel a certain degree of "initiation" is needed before being exposed to the ideas, and being introduced too early can have a negative impact, as it did with Nobuko. Curiosity about death is necessary, but also a degree of being able to really face death and the idea that one day we will die, cease to be here, leave all this – this ego-perspective – behind.
I would also add that a disenchantment with existing explanations and attitudes about death is required. If you're happy with whatever your tradition says or doesn't say about death or don't really care, I say don't bother looking into Tibetan Buddhist theory.
The meat of Peaceful Death, Joyful Rebirth is in the accounts of "delogs" – people who had died, had experiences in the death bardos, but then were revived and were able to relate their experiences. The important thing to note is that experiences in the bardo aren't objective, but projections of our own selves, experience and karma.
Many of the delogs had similar experiences because they are all Tibetan and were taught the same thing about the death bardos, and so that's what came out during their experience in them. So even their experiences themselves, if one chooses to believe these accounts, are not necessarily what is going to happen to everyone after death.
I do think the general framework and stages outlined in The Tibetan Book of the Dead make a lot of sense. The sensation of dying is probably universal – as I mentioned in Initiation, the chapter on the actual initiation has similarities to bardo descriptions, and one of them is she describes an experience which is close to the sensation of dying in the "time of death" bardo.
For people who have encountered this tradition and are positively intrigued or find it familiar, I highly recommend Peaceful Death, Joyful Rebirth. It likely will be helpful with interesting insights.
However, in general, most traditions don't have such an in-depth death tradition, and the vast majority of humanity, like other sentient beings, are just swept through the death bardos uncontrollably, pushed and pulled by the force of karma – their natural beings as expressed through attachments and aversions experienced in physical life – until they inevitably experience rebirth in their next life, with no recall, and no understanding that who they are is informed by what they were.
The later chapters of the book I had to take with a grain of salt. I was wary about the chapter on the Buddhist "Pure Land", which I think is largely doctrinal. To me, describing the pure land is like Christians describing heaven – how the hell do you know? I find the Christian description of heaven ludicrous and unattractive, so describing the Buddhist pure land(s) is equally useless.
I generally agree with the Zen take on the pure land. If the suggestion is that the pure land is some magical, other-worldly place, and not in the here and now, I'm not interested. If it's something to strive to get to or desire, that's kinda counter to the point of Buddhism, whereas if it's about transformation and realization and perspective in the here and now, that makes more sense to me.
On the other hand, by the time I finished reading the chapter, I think I can interpret it in a way that makes sense to me, which is that visualizing the pure land based on the doctrinal descriptions can help in cultivating positive visualized atmospheres.
Finally, the last chapter and appendixes on rituals for the dead or dying are directly linked to the Tibetan Buddhist tradition and The Tibetan Book of the Dead, and whereas earlier chapters might be interesting to anyone simply curious about different views on death, these later chapters are only for people in the tradition. They also don't add very much to an actual reading of The Tibetan Book of the Dead, but offer a watered down version for people without the patience for the whole cycle of writings or can't get through the more esoteric sections.