A true story.
There are many opinions about the maximum duration of an activity. You often see project schedules with activities that span more than twice the reporting period. Some activities even last almost the entire project period. This is possible for some administrative actions, but it is not recommended for other activities.
I will illustrate this with a practical example that I have experienced myself. Ton, a boss in the workshop, was responsible for making a hundred or so large parts for an offshore steel construction project. These parts were almost identical, had an average lead time of four weeks, and, on average, two people worked on them simultaneously.
I had broken down the scheduling into short, manageable activities with a lead time of no more than 5 days. As a result, this part of the project schedule consisted of as many as 700 lines. But Ton wanted it different. He wanted 100 bars, with a bar of 4 to 5 weeks for each component.
After working on the parts for 3 weeks and processing the progress weekly, we faced a sizeable unforeseen backlog. The manager started talking to Ton about lagging behind and working inefficiently. Ton had no explanation; the work went well and efficiently.
Then we filled in the progress together in the detailed project scheduling – which I had saved – activity by activity. It turned out that Ton had trouble estimating the time for all 100 parts, and he had been very conservative. It also turned out that the progress and productivity in many short-term activities were much better than in the first measurements and even better than planned!
Since then, we have worked together for many more years, and the project schedules have become much more production schedules, with even shorter lead times. And reporting progress was also becoming faster and more efficient. But more importantly, we could compare the planned manpower much better with the available people because we had designed it very accurately. And we were able to reduce the 'lost hours.'