He said that the touch should come from a curved finger position, with fast finger action but very light.
Another thing I've found so far that is interesting, is playing really dense clusters of tones that one might hear in post-romantic music of all kinds (jazz, atonal, etc.), the clavichord makes all the tones very clear, even in these dense clusters. It actually makes that sort of playing more interesting, for me, than it was on the piano.