Tourney: Brighton - NS - 07.05.2011

saying that though it should count as a ball joint if it's properly cupped

Side joints are the same as a ball joint, the key thing is seeing the ball "pinned" (mallet covers the ball/pins the ball to the floor).

8.6 – Ball–joints and side–joints are made by pinning the ball between an open end of the mallet head and the playing surface and then dragging it.
8.6.1 – A player that ball–joints/side–joints cannot score until after he makes a pass.