"Running" strictly means you are headed dead downwind, exactly in the direction of the wind, a la monohull. If this is so and you really get a puff (Heavy Air) that requires de powering and you are downhauled and (depends on boat) sheeted hard and travelled out, theoretically you would lessen drive by sheeting in. Personally, I'd consider myself screwed. Sheeting the jib all the way in (as if to choke the main) actually helps but why I dont know because the main is stalled anyway.

What you are probably asking is "Where do I go when I am sheeted moderatelytight or tighter, travelled out all the way and smoking along, and I get a gust? Your point of sail is such that on releasing mainsheet tension, the instant fullness of you sail will heel the boat... and kills speed too. Heading up doesnt do anything for you immediately and may power you up more depending on exact boat and point of sail. Also the inertia/centrifugal deal may do you in, burying the leward hull. Driving off (turning further downwind) is the thing. It begins to stall the main quite suddenly, and this edge is what you want to learn for making good progress downwind. Heavy air is the place to learn downwind technique if you are physically up to it. Once you get the principle, you apply it to lighter air (harder to feel) and you are ahead of the fleet. If the fleet aint around that is OK to, 'cause nothing beats that heavy air off the wind sweet spot of diving off into shelter, coming back up and holding speed, back and forth, rudders only. Dont worry about trapping out off the wind untill you have upwind mastered. It is much harder and less of a payback. If its cranking enough to help, the boat will be surging and maybe burying and the trap wire will be pulling you foreward 'cause you are way back and... whereas upwind the moment trying to overturn you is substancial in relatively light air, so trapping pays, is steadier and you are forward. Off the wind smoothness pays and so sitting on the boat can pay off.

Hope this helps.