I think it's pretty safe to claim that LDS are modern-day gnostics: they believe in a different form of God/Jesus than "mainstream" Christians and claim to possess extra scripture, teachings, and mystical secret knowledge that protects its owner and provides access to the choicest realms of the afterlife.

Hmmm. I believe these things too about myself.

you have your own sacred scripture? Please share.

Nice.

I should add that the word "gnostic" gets thrown around like it was a standard set of beliefs, when it seems to have been a smorgasbord of all sorts of ideas, some of them really kooky.

I tend to think the gnostics were a Christian version of Hellenistic mystery cults, such as Isis or Mithras or Orpheus or Eleusis.

Which is why BRM referred to them in the fondest terms in Mormon Doctrine.

I think you will agree they had no scruple against creating scripture that deliberately immitated earlier gospels and pretended to be based on eyewitness accounts. The Gospel of Judus a prime example. This seems to be a signature trait of Gnostics to this day.

Oh yeah, they laid it on thick. What better way to persuade others to join than to claim "original" apostolic writings?

Early orthodox Christians did the same thing. The Book of Hebrews was attributed to Paul to give it more credibility. It was probably written by one of his followers instead. The Gospels were all written anonymously. The author never mentions himself in any of them, but they were attributed to Matthew, Mark, Luke and John probably for the same reason. There were many other books of scripture circulated by orthodox Christians that did the same thing, most of which didn't make the cut when the canon was finalized, but a few probably snuck in there anyway. Some of the letters of Paul that are in the Bible are thought to have been written by someone else.

It's one more advantage the Book of Mormon has over the Bible. There is an established provenance of the sacred records kept over the years, which the Book of Mormon goes to some length to document.

The problem with most Protestant churches today, especially the evangelicals is that they give the Bible an authority it never claims for itself. Also, the early Christians didn't have the idea of a closed canon as new scripture kept coming out well into the 2nd and 3rd centuries. The later stuff was mostly all rejected by the church eventually, but much of it was in regular use by orthodox Christians at the time and in some cases way into the middle ages.