I suppose most short term traders would be trading the E contracts and with all the intraday trading there wouldn't be many gaps to fill. Not that a gap is that important other than it is easily filled with no activity there that would serve as support or resistance from previous trades. I don't trade Corn and haven't for some time now. If I was to trade it I'd trade the ETF:CORN that is actually a Spread trade that uses 3 futures contracts. Here it is with March Corn overlaid in orange. More than one way to skin a cat.