A Rule of 12 when managing teams?

Over the years I have been extremely privileged to work within some exceptionally effective and successful engineering design teams. No more so than in 1984 when, after graduating with a mechanical engineering degree from the University of Hertfordshire, I joined the McLaren Formula One team full-time; the 7th and most junior member of John Barnard's design office.

At that time 'JB' ruled with an iron fist; the whole office being led by a man who knew his craft and believed that attention to detail was everything. The cars that resulted were jewels and brought a new standard of engineering to F1. Together with Ron Dennis, JB introduced us to the setting of an 'exceptionally high bar' and the need to 'do things properly'. I was also taught 'Rule 1' and 'Rule 2' by my more experienced engineer colleagues: "Rule 1: JB is always right. Rule 2: When JB is wrong, refer to Rule 1!" With a design office that size though, JB could be, and was, on top of everything that went on. He delegated reluctantly but made sure every part designed had his personal stamp on it in some way.. I can still hear him say "Just reduce that diameter by 1/64th Matthew, it looks too big" (Yes, we were still in inches then!) . There was no 'please' of course, that would be superfluous.

The interesting thing for me at this time though was how effective the design team was. Sure JB was a dictator but all of us had the utmost respect for him and a passion for what we did and how we did it. We all had our areas of responsibility, we all 'got on' as individuals and there was little back stabbing - certainly no blame culture when things went awry. Most Friday lunchtimes involved a DO trip to the pub for lunch - not just a social ritual but a great time to all sit around a table, chat about what we were working on and contribute to other design issues if we had good ideas.

With the successes on the race tracks multiplying, thanks largely to JB, Ron Dennis and the likes of Watson, Lauda and Prost (Senna came later), inevitably the design team started to grow too of course: engineers 8, 9, 10 were soon added. The office was expanding rapidly and lo and behold as soon as it grew beyond 12 in number something interesting occurred: We didn't 'all' go down to the pub together on a Friday lunchtime! Instead the office naturally and organically sub-divided into two groups. We couldn't all sit around one table or two joined together any more. At the same time (or as a result?) the culture in the office changed. People became more 'cliquey' and as a result less well-informed of what others were doing and thinking. The office became more unmanageable I am sure from JB's perspective and more difficult to control - which for a dictator spelled the beginning of the end for that way of working. Overall, the design process became ever so slightly more difficult and complex to control effectively.

Over time, more complex cars meant the age of the dictator chief designer in F1 had to end. People kept being added to the design team and new tiers of design team leader management had to be introduced. This seems to be nature's way of ensuring a collective team of people stays manageable... 

So what's the moral of this story? Well, there isn't really a defining one and I'm certainly not trying to suggest that companies do not expand their design offices. These days, an F1 team has over 100 engineers in the DO (as opposed to seven) - still charged with the same job of putting 2 cars on the grid at each Grands Prix. No, the message here, if there is one, seems to be that managers need to be wary of how many people is 'too many people' to make an effective sub-team and the consequences of what can happen if the team grows too big beyond the jurisdiction of any one manager. It seems to me to be likely that when you add the 13th member of your team or sub-team you can now expect to be a manger of two teams: one of 6 and one of 7. My suggestion from observation is that a team should always be kept to be below 12 for any one manager.

In conclusion, I should probably do some due diligence and find out whether there has been any scientific research done in this area to back up my empirical observations. I'm sure there must have been. In the meantime I will trust my own judgement and continue to believe in my 'Rule of 12'. After all it seems the RAF had the same idea (there were typically 12 aircraft in a fighter squadron during WW2) and many sports teams are 12 in number or less... So, does that mean rugby team players don't all go down to the pub together to talk tactics or would they benefit form 2 managers? Whatever, perhaps I should preach my 'Rule 12' to any followers: MJ's rule of 12 is right!