Here's a decent article consistent with what Mil is saying. Interesting idea, that the time out actually dilutes the responsibility, making no one ultimately responsible. Not the best resource, as it is a liability group, thus not representative of the nation as a whole. I doubt JCAHO would ever release data contradictory to its goals, though.
At the same time, reading the original JCAHO report, I didn't see any mention of drug use being a factor in any of the reported cases. Mostly communication issues. I think if anything, it is money and the bottom line that has created this problem. Surgeons, staff, etc. are driven to work faster than ever, squeeze more cases, etc. Leads to haphazard behavior.
I can't even remember which of my COPD'rs on a vent has the PNA v. CA. I could easily forget which leg to cut if I had 4 BKAs in one day.