"Commute" joke

A recent college graduate took a new job in a hilly Eastern city and began commuting each day to work through a tiring array of tunnels, bridges and traffic jams. To make the task less onerous, he invited several of his coworkers to share the ride. He soon found, however, that the commute continued to get more stressful, especially the trips through the tunnels.

He consulted the company doctor. "Doc," the frustrated commuter complained, "I'm fine on the bridges, in the traffic, in the day and at night, and even when Joe forgets to bathe all week long. But when I get in the tunnels and I've got those four other guys crowded around me in the car, I get anxious and dizzy and feel like I'm going to explode."

? Without further analysis, the doctor announced he had identified the ailment. "What is it, Doc? Am I going insane?"

"No, no, no, my boy. You have something very common in these parts."

"Tell me! What is it?"

"You have what is known as Carpool Tunnel Syndrome."