Also skeptical because they reports don't distinguish between types of shift work. There is a huge difference between working "straight swing/night shift" (always on the same shift), "rotating shifts" where you never get a chance to settle in to a schedule because every couple weeks everyone is rotated to another shift, and even working random shifts like the air traffic controllers do where they are working all three shifts during the course of any week.
Your body can adjust to straight shifts - I worked for several years on a straight 11-7 night shift and never had any of the problems they mention. Coming home in the early AM before the boy-toy left took care of the sexless part. :) My sleep schedule shifted to two 4-hour sessions (11AM to 2Pm and 6PM to 10PM) ... waking up to have dinner with the boytoy and head for work. I had plenty of time in the morning and late afternoon to do things ... I loved it. We had a evening and night shift that was self-selected ... most of the night shift were early risers when not on night shift, not ones who normally stayed up until 2AM. WE had convinced our bodies that we were getting up just "extra early". The swing shift (3-11) had most of those "owls".
Rotating shifts ... suck! You barely get your schedule set in and are sleeping well again when they yank your inner clock out by the roots and toss it in the trash. I've worked them, but only briefly. No one on ANY of the shifts is at full efficiency for the first couple of weeks of the new schedule.
Random shifts, double and triple shifts ... utterly stupid! There's enough research on sleep and efficiency and biological clocks to convince me that these are designed to ensure maximum inefficiency. I've coped with a few extraordinary work sessions ... three straight days (that's 9 work shifts) during a blizzard when the rest of the staff was snowed in, but we were taking frequent naps to keep our efficiency up. If you expect to get efficiency on really long or random shifts, you need naps.