I agree that SBTC probably means Saved By the Cross, and maybe ALSO means something else, like Subic Bay Training Center and ALSO maybe it has additional meanings, and was thought to be a good signature because it encompasses, possibly, a lot of things.
In a required political science class one time, which concentrated on terrorism, we learned that violent extremist personalities come first before the choice of a group to join to try to justify it.
In other words, someone at another site, another forum, had jumped to a conclusion that one pervert in religion means that to normally intelligent people it's a bad influence. No, some crazies just pervert it. (BTK for example?) The test of whether a thing is true religion, and extreme nut cases wouldn't think of doing any morals test, is Does it harm even one person, even one of the very least? Killing or even illegally judging others is forbidden.
There's a book by, I believe, Rokeach, about three guys in a mental hospital trying to over-compensate for inferiority feelings by deluding themselves they're Gods. I believe the title is something like "The Three Christs of Ypsilanti", a SE Michigan mental hospital and university town. Another book suggested that very extreme personalities come BEFORE choosing an organization with which to try to jusify extremism. Maybe not always. And we hear rumors on the news that some in nonChristian religions are born into it, taught from childhood to kill, with wild promises of so many virgins for them in the afterlife. Are they then mentally ill? Truth may be somewhere in between?
There were people from terrorist nations in the university at Boulder, but they wouldn't know to sign a note Saved By the Cross, right? And would not know the Ramseys as well as this killer or killers did. The uncanny resemblance of the Barnhills' walker to JAR was probably no coincidence, but part of the staging to try to pin this on the family, like the forged RN and the dictionary, and any other staged clues. The walker probably was meant to be seen, in broad daylight, by neighbors. Stanton's hearing metal hitting on concrete from across the street....would a golf club have been that loud, or wouldn't the tool have had to be something bigger and heavier? 15th St. was not wide, but windows over there would have been closed and it was, I believe, about 1 AM (?) when most neighbors would have been asleep. Stanton was awakened by his wife who'd heard a scream and wasn't sure if that was just a dream. He definitely heard the metal-on-concrete beating going on.