Force Choke

ASK FANTASY FLIGHT 

Q: If C-3PO (Core) is sacrificed to cancel the effects of Force Choke, can an additional Force Choke be played in the same turn, or does the once per turn limit still apply because only the effect of Force Choke is cancelled, not the event itself?

A: The event was still played, only its effects were canceled. Therefore, the limit prevents another being played that turn.