I have some understanding of this "shaking" principle. However my view is that all too often it is manifested by excess shaking of the body, when what is being imparted is a hydrostatic shock as I have discussed in this article: http://dandjurdjevic.blogspot.com/2008/06/visible-power-vs-real-power.html
and illustrated in the video embedded in that article.
"Lightning" is an apt, if grandiose, description of how this type of strike should feel (with a full power blow, of course) because the hydrostatic shock is transmitted to the nervous system. This may sound far-fetched to those who haven't been at the receiving end, but imagine a "winded feeling" from a blow on your chest - not on your solar plexus (which is how I've experienced it in sparring with my teacher).
But again, I think that the "shaking" feeling you might produce in your opponent is often being unnecessarily produced or replicated in the striker's body...
Hydrostatic shock techniques are indeed "internal", but the "external" shaking of the body is not.