I totally agree, ED, you have to have some working knowledge of the area you are managing. In our Industry even if it is just a good "Mechanical Apptitude" is better than nothing.

Management or "Coaching" skills are the same no matter what the business is, But the "Specifics" of that business combined with good
"Management/ Coaching skills makes a great manager, especially if he has the willingness to learn the specifics and work with a GOOD TECH.