I have to admit that I have never seen anyone catch a catfish quite that big, but I've seen them pretty close. When the fish is so big that it takes two adult men to get it into the boat, you know it's a monster. One thing I've seen them do with the big ones is point them head first into a burlap sack and let the fish swim into it. Makes hauling them out of the water a lot easier.
I don't think that picture was taken anywhere near Oklahoma. All of the big catfish I've seen in this region are more of a uniform blueish-grey color.
Really I've always questioned the point of this hobby. When catfish get to be that big the meat gets pretty nasty tasting. I know this is more of a thrill seeking thing, but those guys eat them too. Yuck.
-S