Helped my understanding but not entirely

Very helpful, couldn't have made it through GR without it. should have built in a spoiler alert system however.

Per combattere la naturale tendenza al parossistico onanismo di ritorno che assale inevitabilmente anche il più adulto e sessualmente equilibrato dei lettori nella fase post-coito con L'arcobaleno della gravità - non solo i lettori ma anche paludati critici e brillanti menti accademiche a sfogliare la sterminata bibliografia critica, si va ad esempio da "Male Pro-Feminism and the Masculinist Gigantism of Gravity's Rainbow", a The Vietnamization of World War II in Gravity’s Rainbow" passando per "Orphic Contra Gnostic Religious Conflict in Gravity's Rainbow" senza dimenticarci di "Queer Sexual And Textual Pratice: The Postmodernist Poetics Of Pynchon's Gravity's Raimbow" solo per citare qualche goccia dell'oceano - la classica guida di Weisenburger si presenta come un ottimo antidoto con il suo lasciar da parte ogni tentativo di interpretazione del testo, ma fornendo una dettagliata ricognizione, capitolo per capitolo - il riferimento è la prima edizione Viking Press - dei riferimenti e le fonti utilizzate da Pynchon. Migliorabile l'indice finale che sembra un retaggio dei tempi in cui "tutto si faceva a mano". Ma in fondo bisogna esser un po' luddisti per apprezzare il Nostro, al diavolo il word processor!

Very thorough, if you want to get all the details of GR this is very helpful though honestly near the end of GR I was so tired of the book I didn't really care what mandala or esoteric quote Pynchon was alluding to...

This Companion was extremely beneficial in reading Pynchon's novel, especially giving reference to the social context and pop culture allusions that appear on nearly every page. However, I had to often set it aside, only referring back to it every so often since there was so much information that it impeded my forward progress in the actual book. I would recommend it to all readers, but it will come in handy the most on a second read. It should be noted that a first time reader may want to skip any commentary of the chapters as quite a bit of plot that won't occur until much later appears before each chapter. Well worth the money, a lot that I learned from reading this would have been equally interesting without Pynchon's novel as a reason to seek it out.

An excellent resource to see the subtleties.

B/B+

Docked the grade and rating due to there being at least a couple inaccuracies in the chapter summaries (imo a cardinal sin when it’s a guide to a book as dense as GR, because a lot of people struggle with the plot of this book and being inaccurate will only hinder those types of readers).

Anyway, I did enjoy this a lot. This was my 3rd read of GR and my first read done with this companion. I read the chapter summaries before reading the individual chapters, then read the chapter, then read the annotations.

I do wish this book was longer and that some of the stuff, like all the Kabbalah references, were explicated on more than they are. I also think that all the annotations about aspects of the Tarot both could’ve been longer and more in-depth.

Clearly written before the times of the internet ...

I lost all faith here:

V71.11, B81.35: ,,,,, "tyrosine" (an unknown and doubtless fictional substance...) ...

How much can one trust the rest of the book ... :-)

Indispensabile come supporto alla lettura del mostro... un piccolo neo: GR companion si limita a fornire dettagli sulle fonti e sugli eterogenei riferimenti extratestuali di Pynchon, mancando completamente ogni spunto esegetico per penetrare -anche solo superficialmente- alcuni dei misteriosi strati semantici del testo... Dommage (ovvero /que sorte!/), la soma dell'interpretazione rimane interamente sulle spalle del lettore.

This is really only a useful companion to Gravity's Rainbow on one level - if you are going to want every mythological, pop culture, and Kabbalistic reference explained as you read the novel. I was hoping for a broader, more connected commentary on the characters, plot, and themes; deeper understanding, not minutia. Ah well. I learned a lot more about German mythology.

GR companion is a valuable resource for those who have already read GR once or twice. I wouldn't use it the first time through. There are good points about the timescheme of GR and details like April Fool's Day falling on Easter Sunday in 1945, which implies the whole book may be a joke, like Melville's Confidence Man--the work that GR most resembles. The detail work on Pynchon;s sources is of course excellent, but I am not learning as much as I expected about the characters. What would have helped is a kind of Dramatis Personae and a threading of the different plotlines they follow. Perhaps an internet resource has this covered, but it is the central challenge of the novel, which introduces and then drops certain people, sometimes for hundreds of pages. Why are we hearing the story of X or Y or Z, when will we be asked to draw on this knowledge again? Anybody who can make that clear has really cracked this recalcitrant puzzle for good. It's nice to have GR remain mysterious in some ways of course, but if you're thinking of using it with students and discussing it like Ulysses and Moby Dick, then you will need resources like this and possibly a few others.

There are multiple companions out there and I think even a companion's companion which is fitting in dealing with Pynchon that in referencing GR's rabbit holes this companion sometimes references the companion's companion inside of those references. I haven't compared companions, I just picked this one out because of solid customer reviews. Weisenburger's companion is easy to use and works with the Viking, Bantam or Penguin editions of GR.
One of the most helpful starting points is that each episode has a brief paragraph loosely describing time, place and characters and sometimes a very loose description of the key action or event of the episode. I found these episode intros were invaluable and did almost nothing to detract from my own interpretation or decoding of the scenarios and movement of the episodes, they simply helped bring an ever so slight but totally invaluable framework out of the mist for an instant long enough to take a bigger bite and feel a fleeting and deceptive sense of solid ground as I stepped into each mini-world episode.
I felt the same about the references/research and help with the rabbit holes. Without these you just can't break the surface of GR. You could read every reference and footnote in this companion and it would still only be the refracted light off a handful of needles in a haystack, a barn full, no, a world full of needles piled to the sun. In other words, this companion does no harm to one's creative interpretation of the text but I would argue that it greatly hones in the readers engagement with GR.
Once in a while Weisenburger takes a stretch too far or a liberty that seems to stem from his enthusiasm and obsession with the text but he never "explains" points or deeper meanings, at least not that I came across and that is of course a good thing, the great fun of Gravity's Rainbow is falling down the rabbit holes which the companion helps you slide down into and unravel via facts, histories and all manor of sources and then making the connections from abstracts and disparity once you're way deep down in there. Perhaps some lit nerds, photographic memories and tenured literature profs that have been living solely in their antique book office for the last 40 years have a head full of these worldly obscure infinite-subject-matter facts and histories but most of us don't. In which case the companion is ideal. You can get in and out quickly or take trip down in there just like the rabbit holes invite you to do. Weisenburger gets a little crazy on a few of the "part" intros and they turn into WTF critical theory lectures about god knows what but that's the nice thing about the companion, you use it as you please and thats just a few pages out of the nearly 400 page companion. Most of the companion reads like a reference text book or technical manual gone mutant and come to life (in a good way). Also there are a couple cool maps in the center of the book charting Slothrops journey and a few well chosen pictures of the bomb development sights in Germany.
The companion in itself is an impressive feat as an invaluable scout to one of the most complex and epic accomplishments in American literature.