The reason I like video, and especially RightView Pro, is that you can SHOW a kid what they are supposed to be doing - from many angles of view, in slow motion, frame by frame, or whatever. Using "catch phrases" and trying to explain something as complex as a swing with words can be VERY confusing, or at least it is to me. Today's technology is FAR cheaper than it was just 10 years ago. "A picture tells a thousand words" is now my favorite catch phrase.
I just put A-Rod or Manny (a pro) on the left side of the screen, and the student on the right. I step their swings through, stopping at key swing points. Then I just let them do a "self analysis" - I have them tell me what they see, how they compare and what they think needs to change. All I need to do is give them hints at methods to fix it. Every kid is different, so they use quite different cues to arrive at the same point. I try to avoid using terms like "keep your head on the ball" (wouldn't that hurt anyway?), "hands inside the ball" (too vague), etc. I guess I'm just a fan of "visual learning" - or "show me, don't tell me".