Agree with you. Hardest part of learning to lead is learning to delegate, if you have been a individual contributor. There is fear attached to it, fear of loosing control, fear of others not contributing as diligently as you did. But one can learn it through practice.
I finally got access to the Docker For Mac beta. My initial impressions are extremely positive. With Docker packaged so well for end users that leverages native OS X virtualization technology, a new era of local Docker development is here.