Consensus view within the Los Angeles tapehead community is a little different. I read Helter Skelter at 12 and watched the movie at 13. It's certainly lurid. It's also nonsensical. Sebring and Frykowski have both been named by several authors over the years as suppliers of narcotics to actors and musicians in Hollywood. A loose-knit network of stars that included such names as Mama Cass and Steve McQueen, as well as Polanski and Tate, whose house at Cielo Drive appeared to be a base for some of the dealing.According to Schreck's research in the Manson file, what transpired at Cielo drive in the early hours of August 9th 1969 was the bloody consequences of a turf war between ambitious small-time drug dealer Tex Watson and established suppliers Wojciech Frykowski and Jay Sebring over the lucrative Hollywood drug scene.
In his kind of autobiography (really a book by Nuel Emmons that is based on notes from conversations with Manson from prison (that I read as a teenager, so my memory is hazy to say the least)) Manson himself sort of verifies the drug theory. He makes the claim in that book that another one of his family killed another drug dealer up in the Bay Area, and in the course of that murder the dude (whose name escapes me) did a bunch of writing in blood ("PIG", etc). Those details were never released in the press, so when they did the next murders (for ambiguous reasons that are never really fleshed out) they recreated some details in order to make the cops think that they had the wrong guy for the Bay Area murder. According to Manson, the cops in LA apparently never spoke to the Oakland or SF cops, and not a second thought was given to the serial killer ruse. Just an interesting aside.
I don't believe the race war explanation and am torn between the drug and record deal theories. The one thing that doesn't fit for me about drugs is that would not account for the LaBiancas. I read the book at about the same age too. These days a lot of parents probably wouldn't even allow their kids to read such a "gory" book. I also used to take Benedict Canyon home and after a night of drinking I decided it would be a good idea to drive by Cielo Drive. Not sure who lived there at the time but it was still the original house and they had left the gate open so we drove right in. No security lights came on so we got out and looked around for a few minutes. Pretty creepy thing to do.