Two great white sharks swimming in the ocean spied the floating survivors of a sunken ship.
"Follow me, son," the Dad shark said to the Son shark. They swam to the mass of people.
"First," the Dad shark instructs, "we swim around them a few times with just the tip of our dorsal fin showing."
"Like this, Dad?" the younger shark asks.
"Well done, Son! Next we swim around them a few more times with all of our dorsal fin showing."
"OK," the boy says, really getting into it.
"And only now do we eat everybody."
And they did, eating all the terrified humans.
When they were both fully sated and gorged, the Son shark asked Dad shark, "Gee, Dad, why didn't we just eat them all right away? Why did we have to swim around and around them in circles first?"
Well, son," the wise Dad shark replied, "because they taste a whole lot better without all that crap inside!"