I've seen that famous intro to MI5.
Or that sitcom "Friends" commercial.
Or lets go back to that famous intro of The Brady Bunch.
Why am I having a difficult time doing it in Vegas video?
You know, that checkerboard like effect of sliding video frames or two different video footage/frames splitting the screen.

Anyhow, I don't know what that's called, but is there a tutorial?
Or plugin software?