[Adam]

Originally Posted by Rob1968

From the camera's angle, at full speed, the contact appears to be on the torso, of the defender. At slow motion, the contact appears to be on the lower portion of the defender's body, and the head and shoulders of the ballhandler appear to be past the front of the defender's torso.
The angle from the calling official's position could easily coincide with that statement, and the block call could be justified.
There also seems to be an apreciable amount of embellishment of the result of the contact, by the defender, i.e. an attempted "flop".

Head and shoulders is a rule of thumb, it's not a hard/fast rule to define a block. It works well when both players are moving, but even then isn't definitive.