Here are the lessons I have learned from my second CMMI L2 appraisal, not all of them are technical:

1) Let actions speak about you and don’t speak about yourself; doings are more respectable than sayings. Most people hate who speak much about themselves.

2) Dictatorship: If you are a team leader and unable to facilitate team discussions or reach consensus, this usually reflect your dictatorship style or the mentality of win-lose. As a team, everyone must focus on win-win relationship. We should believe we are strong because we are different and being different means we have a great chance of building integrated vision.

3) Treating people should be smooth, not just when things are easy but also with hard issues and when we feel angry. IMHO this is the measure of person kindness and professionalism.

4) You can always ask people for annoying things as long as you treat them with great respect and let them understand your intention. As example, if you in a critical meeting, you can ask a person to leave the room, or to turn off mobiles as long as you say it properly. On the other side, some people feel great when they have the chance to hurt other people.

5) CMMI interpretation is quite flexible, you can tailor it greatly. Remember that CMMI is a model not a process. You can use this feature to hurt your business or to help it.

6) Using tools improperly can lead to a very complex baseline taking and reconstruction. So always use tools the right way.

7) Tools come with their own complexity. Use sophisticated tools only to solve complex problems. Generally use the simplest tool that is good enough to manage your current problem. Use the right tool for the right task.