I am starting to think you are just a troll looking to get a rise out of people with these threads you start. If you are serious then go ahead and make that easy trade as you say. take a position and post your entry price.
I agree that there's no reason to sell Wheat now, but I thought the massive bids every time there's a limit up is because you get pro-rata fills (proportionate according to your % of the bid size)? So it's not "real" demand if you catch my meaning, even though you can hit it if you'd like.
If you are going to short, I would short the July 08 and not the May 08. The old crop is like a tinder box that is ignitable on any sniff of a supply squeeze. At least by July, there will be new crop coming in. Still think the risk reward is poor for a short at this point.