I've never had the name expained to me, but my initial thought is that as you turn into your opponent to deliver the elbow strike to his face, you are gazing along the horizon. The act of turning to deliver the strike sort of follows the horizon.
Then, when you step out and execute the wrist lock and follow up with the kick, that action of stepping out and turning is again sort of gazing along the horizon.
I know, it's a little forced, but I can see the spirit of the technique in the name.
I just learned this technique two weeks ago I don't have my sheet with me, but I believe my instructor called it crossing the horizon. I could be wrong about that, and I know lots of schools have different names for techs.
Anyway, he said it was named this way because the initial elbow strike goes up and over the outstretched arm of the attacker. Sort of like crossing over the horizon. Supposed to be a reminder to get that elbow up high and over the attacker's arm.
That sounds right to me. EPAK has a technique called "Circling the Horizon", which refers to punching around/over the incoming straight right of the opponent (the "horizon" the we are "circling"). A great concept that I apply all the time in sparring.
There is also Retreating from the horizon and Diving/driving hawk which are different variations of passing the horizon.....personally I enjoyed "retreating from the horizon" but found "diving hawk" to be repetative.
After thinking it over a while I think the name comes from passing your hand over the horizon (almost like passing your hand over a pet) This happens when your turning over the opponent to expose the ribs. I guess that's why "retreating from the horizon" steps away from the opponent as your turning him over (exposing the ribs or armpit).
I know the initial movement of couter-grabbing and elbowing are important but I think the main objective of the technique or where the technique was built out from is the demonstration of the ability to manipulate the opponent and expose weak points with just one hand and correct body movement to assist.