When performing pixel-precise movements with a touchpad, the 'rawsample' averaging that takes place can cause the pointer to move non-intuitively. For instance, moving the pointer in one direction and then trying to move "back" a small amount may cause the pointer to continue moving in its original direction. Because it is not very difficult to move the finger a small enough distance to correspond to a single digitizer unit, the averaging effects become noticible and impair precise positioning.
Linuxwacom has moved from Sourceforge to Github. If this is still an issue please reopen the bug there.