This was an excellent article. It reminds me a bit of a story I heard years ago about a power utility company in the mid west that wanted to reduce accidents a

This was an excellent article. It reminds me a bit of a story I heard years ago about a power utility company in the mid west that wanted to reduce accidents among its line workers. They looked at all their line crews, and found one team with a significantly better safety record than the others. They sent out a consultant to see what was going on and found that this particular crew was composed entirely of smokers. Before each job, they'd park their truck and have a cigarette while talking it through. Said consultant came back with this information and the company instituted a detailed pre-job planning worksheet that each crew had to complete. From what I remember (I can't find the link anywhere - I read this 15 years ago and Google is no use here at all) the net effect was to worsen safety across all crews, while reducing the standard deviation between crews a bit.