I read John Maeda's blog on Second Law of Simplicity a while back at http://weblogs.media.mit.edu/SIMPLICITY/archives/000160.html
It reminded me that time saving can be a parodixical two-edged sword. Back in the days when we needed a minicomputer to run CADCAM system software our design office ran 4 CAD terminals off a well endowed Dec Microvax II. In order to save time running toolpaths to produce manufacturing moulds, one of the designers would start the calculations running just before lunch, knowing that it will take at least 40 minutes before the final toolpath visualisation would appear on-screen. Off to lunch we would go and about 45 minutes later we would return . Our cunning CAM man would look at the visual result and cheer or swear depending on the succesful outcome. If a swear he would adjust parameters, set it running again and settle down to do his emails. So the cycle time for tasks settled into a rough 40-minute rhythm, which ties in with our concentration thresholds, coffee break desires, etc.
Then one day I signed off a request for a pair of stand-alone workstations. When they arrived they were so fast we nearly cried. A 40-min toolpath now took 7-8 minutes. This meant that as the same person got to lunch he hit the toolpath execute button but remained alone in the office to see the result, in case the parameters were not right. As we finished our lunch he would appear. "Sorry the toolpath calc kept crashing, so I stayed till I was sure we were there." I'll grab a sandwich and come back with you." Soon people began to get headaches from eyestrain as they spent more time at their screens. Yes productivity was better but we had to change our procedures to ensure the unintended consequences were managed. As design technology got better and better we had to redesign people's jobs to ensure we remained highly effective; we forgot productivity as a measure!