Vim's the worst for this, since it has a mix of the two.
hjkl is positional, but then iasdftweruvnp are all memonics, and I'd want to move those. (Insert, After, Substitute, Delete, Forwards, unTill, Word, End, Replace, Undo, Visual, Next, Paste).
Actually, I guess most of the keystrokes are placed by meaning, not position.