Well someday maybe we'll meet and I can see how this list functions. For me, basic = kokyu. Next comes improving the kokyu via ki development. That's obsessed me for 3 years and has gotten some interesting comments from partners. Next.. well I better start meeting others and seeing what amazing stuff they are doing!
ps by kokyu I mean "putting the center into the hands" and that sort of thing, which is why the comments in this thread don't seem to suggest a specific meaning for "elbow power" to me.
O.K. How about this? If that's your reality that's good. So try this: When putting centre into hands put it into tegatana. Now practice cutting in various directions and notice the elbow and what it's doing as part of your action. If you push tegatana upwards for example up your own centre line, like raising a sword, you will notice what happens elbow wise. This could then be called a way of using the elbow but to me it's a result of using tegatana from centre.
Thus I say it's not a basic but it is something to be aware of and if your aware of it you can use it when necessary. But still it's a result of moving from centre or koshi etc.