Very novel !!!
Dynamic stability increases with faster speeds through the water and would most certainly retard and dampen the rolling period. Such could also have automatic control surfaces and pitch angles similar to the current International moth 'foiler'.
http://www.youtube.com/watch?v=IcOzUn3-mrI ..... that little 'black whisker' hanging down from near the tip of the bow at 1 min. 50 seconds into the video is the 'control rod sensor' for the automatic hydrofoil 'pitch control'.
However, an additional 'daggerboard' etc. far enough away from the keel or CB foil and located in 'undisturbed flow' would do the exact same thing as regards 'stability' .... tried even on Americas Cup boats (Tom Blackaller ~1987) with quite poor results as the increase of drag affected speed.
The more modern trend is to build wider beam boats with very flat bottoms for the exact same dynamic stability effect.
The super fast ILYA scows (normal speed @ 15-25 kts), with retractable twin 'bilge boards' (2 centerboards each located near the hull sides and set at a slight offset angle from the vertical) have been doing this since the 1890s !!! The 'windward' board is usually retracted when sailing due to the excess drag the second board causes.
http://www.youtube.com/watch?v=zEnMGV1TfkQ
http://www.melges.com/boat.php?p=pages/boats/A-scow