Visible crew/equipment: While Tony and Paulie are alone aboard the rented boat, Tony questions Paulie about being the joke leak. When Paulie denies it and says, "It wasn't me, Ton'... That's right," Tony lifts his beer and drinks. It then cuts to a wide shot of the swaying boat, and at the top of the screen, we see a hand move atop the steering wheel at the helm; we even see the top of the hair of this crouching crew member as the wind blows, right before this shot cuts away.
Visible crew/equipment: At the hotel's complimentary breakfast buffet, Paulie loads up a plate filled with Danish and Yoplait for the drive down to Florida. It then cuts to the Wycoff Therapeutic Center, and at the start of this first shot, we can see the boom operator (papers in the back pocket) with left arm up, at the right side of the screen. The reflection of the moving boom pole is also visible over the fireplace mantle.
Answer: That's not Jimmy, just a look-a-like. Jimmy's short and stout, the guy in "Christopher" episode is tall and medium built. The hair is also different.