But why does the smaller writing under the "X" say "Transition appears over 5 frames"? Anyone?
Because it's a marker on a video tape containing a pre-built transition. "X" plus 5 frames = where the transition begins. This wasn't intentional. It was a TV gaffe, nothing else. I despise CNN as much as anyone else, but save the paranoia for the real stuff.
In a TV control room, there is a "preview" channel and a "program" channel (a bit simpllistic, but bear with me). For anything involving motion, the director begins the animation on the preview monitor, and then switches what you see on the screen over to that at the appropriate moment. Sometimes, there's a circular countdown like the ones you see on old movie reels. Sometimes, it's bars and tone with the seconds ticking down. I've never seen a big black X, but it doesn't surprise me much. I have seen bars, countdowns and static on screen many, many times when things get a little out of sync. It happens far more often on cable news, which has 24 hours to fill, than on the Big Three, where they have all day to plan a half hour newscast.
Whatever the type of countdown, there's something to let the director to know when he should push the button. That's how you get a smooth transition without a stutter or a black screen.
As far as Rush's challenge to Fox News, I doubt they can prove how easy it is to do intentionally, because it isn't easy to do intentionally. I have never seen any piece of control room equipment with a "flicker intermittently for two frames at a time" button on it. Unless someone managed to keep his fingers on two buttons at once, alternating between them, while having a grand mal seizure, I don't see how this is operator error or an intentional prank. There is no control room equipment designed to do that, because it's not a feature anyone wants.
And spare me the "subliminal message" jazz. First, there's no clear scientific evidence that subliminal messages are at all effective. Second, you're going to tell me that if it's going on, in an era when it's easy to zoom in on a single frame of video, no one has noticed before? Or that dozens (to be extremely conservative) of people could design, build, and operate a subliminal message system for CNN without anyone leaking word?
Even if -- for the sake of argument -- CNN went to all the effort to build in that capability and then never used it, do you think they'd bust it out for a mid-afternoon speech by the Vice President instead of during the State of the Union, when the audience is twenty times larger and the stakes are higher? Or that they'd use a cryptic black X with "transition begins after 5 frames of black" in unreadable type under it, instead of something simple like "LIAR" in big bold type?
The most plausible explanation, to me, is that some piece of control room equipment spazzed (to use a highly technical term) and started scrambling the signals. An intermittent error that would be difficult, if not impossible, to reproduce. If you've ever worked with very large files on any type of computer, you'll know that performance gets erratic after a while and errors become more common as you go along. It helps to reboot every now and then to reboot the caches and let the machine run disk and memory diagnostics.
I've had to chuckle at some of the attempts in the last couple days to read a deeper meaning into the X, whether it's a call for assassination or "Manchurian Candidate"-style brainwashing. Please, folks. Sometimes an X is just an X.