When you are deeply involved as the Manager in charge, it is very difficult to lead a workshop yourself, i. e. do the facilitation.
The permanent change of the "facilitation-hat" (I'm responsible for the process of the meeting) to the "Manager-hat" (I have interests in the topic / project) is complicated and costs you a lot of effort.
For such cases I'm often requested to act as a pure facilitator. I prepare the workshop, lead it to its objectives and take care that the participants stay tuned and do not waste their time.
"Project Management from the practice" is always in the back of my mind and if applicable I give input into the meeting. Topics range from finding the optimum process between Departments, to three-day retreats with 30 participants, to resolving conflicts between you and your customer.