A traveling salesman visits a small town in rural Texas and sees a circus banner reading: "Don't Miss The Amazing Texan". The salesman is curious, so he buys a ticket. The tent goes dark. Suddenly, trumpets blare, the lights come up and all eyes turn to the center ring. There is revealed a table with three walnuts on it. Standing next to the table is an old retired cowboy. Suddenly the old cowboy unzips his jeans, whips it out, and smashes all three walnuts with three mighty swings! The crowd erupts in applause and the elderly Texan is carried off on their shoulders.
Ten years later the salesman visits the same little town and he sees a faded sign for the same circus and the same banner warning "Don't Miss the Amazing Texan". He can't believe the old guy is still alive, much less still doing his act. So he buys a ticket.
Again, when the center ring is illuminated, there stand the table and the old cowboy. But this time, instead of walnuts, three coconuts are placed on the table. The old guy stands before them, then suddenly unzips his fly, whips it out, and smashes the coconuts with three amazing swings. The crowd goes wild! Flabbergasted, the salesman requests a meeting with him after the show. "You're incredible," he tells the Texan. "But I have to know something. You're older now, so why in the world would you switch from walnuts to coconuts?"
"Well," says the old cowboy, "my eyes ain't what they used to be."