It looks like there is tilt. But there pictures in the article do not show the top view of the 8A piece. That could be the rotational piece?
Using mb and mc coordinated (in one direction) + ma you have xy shifting
Using mb and mc in opposite directions (e.g. mb to the left and ma to the right) you have a rotation
Combining both motion types you can counteract any type of rotation and shifting (within the limits of the acceleration sensor / electronics / actors).
Tilting the sensor is IMO not very helpful because it changes the focal plane. Maybe interesting in macro where you can do some tilting but I think the majority of cases will be done first!