The biggest portion of published Golden Dawn and RC et AC documents (assuming that Stella Matutina can be considered Golden Dawn) was published by the late Isreal Regardie. His work has became the thirty-six inch rule (or twenty-four inch rule if you are a Freemason) that many people judge what is and what is not Golden Dawn by.
Unfortunately, there are a few problems with using Regardie as our benchmark for what should and should not be in Golden Dawn.
The first of which is that the branch he belonged to, the Stella Matutina, was a later offshoot of the original Order; it had roots in the original Order, but some changes had been made to the rituals and lesson plans. Yet many people consider his documents to be the proper standard despite this.
The second problem is that Regardie was a mere ZAM (Zelator Adept Minor 5=6) when he left the system. The few higher documents of the THAM Grade and of Waite's Holy Order that he collected and published are not enourgh to judge what the higher Grades of the Golden Dawn should look like. Yet many people consider his documents to be the proper standard despite this.
The third problem is that he picked up a lot of ideas from Crowley. Now, personally, I have no problem with Crowley in small doses, but Crowley's ideas belong more properly to his own Order, the AA, and to OTO; Thelema is not part of Golden Dawn; at best it is a sister system. Yet many people consider his documents to be the proper standard despite this.
(Though I will admit that the Thelemic Golden Dawn has combined the two quite nicely. I do not say that as a member of the TGD, though I might still be a member of that Order depending upon how you view my parting with that organization.)
(I still need to study the material of Open Source Order of Golden Dawn before deciding if they are combining the two in what I consider an acceptable manner; acceptable being defined as "does not make me run for the hills.")
The fourth and most important problem is that Regardie only attended his own initiations. He attended no lectures, had no exposure to the oral tradition, had no contact with the other members of his Order. He had only the Stella Matutina documents to judge what Golden Dawn is or is not. Yet many people consider his documents to be the proper standard despite this.
All this translates into a situation where people are using the documents that he had published to judge a system that had more branches and more differences in it than he was aware of. His Golden Dawn is not necessarily my Golden Dawn; nor is it necessarily yours either.