I previously described an approach to implementing inertia processing by averaging positions to extract velocity from manipulation. However, this approach could result in discontinuous velocities when transitioning from manipulation to inertia.
While implementing multitouch manipulation processing for this project, I "smoothed-out" manipulations using a basic dampened-spring algorithm. Rather than extracting velocity from position, this approach conversely relies on calculating velocities to extrapolate positions. This neatly solves the problem of discontinuous velocities since I always know the correct velocity at the point at which manipulation ends, and is also a much simpler approach.
Using "stiff" springs ensures gestures such as flicks lead to rapidly increasing velocity.