Can you please expand on your April 4th answer? This has sparked a lot of discussion in the referee community on what constitutes control, or a mis-kick.
USSF answer (April 5, 2012):
Not sure why there should be any discussion at all. This matter is addressed in the entry-level referee training courses and there has been no change in policy or interpretation or guidelines: If the opponent who does not have the ball under control (i.e., clear possession and the ability to play the ball deliberately to a place to which he wishes it to go) misplays, misdirects, deflects or miskicks the ball, he has not affected the status of the player who was in the offside position when his teammate played the ball.
In any event, the decision is solely “in the opinion of the referee,” based on all the “facts and circumstances” of the event — all of which means that no formal, official, concrete definition is possible (or even desirable), only guidelines.