Since University I've worked for accountants, Landmen, Business Analysts, and a half dozen flavors of engineer.
I think that the assertions above that an Engineering Manager must be an experienced Engineer are just nonsense. The best boss I ever had was an experienced engineer, but she didn't have nearly the engineering experience as the worst boss I ever had. The best boss I ever had is ending her career (after a stint as an on-campus recruiting manager) as an HR rep, and I will give long odds that she is superb at that as well. I have nearly zero respect for HR, but if the function must exist I'd like to see people with integrity in the role.
I think of a boss as a Tom Terrific hat (cartoon from the 1950's, the hat is a funnel). If you turn it with the small side up, most of the raining BS is deflected. If you turn it with the small side down then it becomes a BS concentrator and the underlings get too much crap and the upper management hears too much nonsense.
As I was reading this thread I was trying think of the characteristics of good and bad bosses that I've had or worked closely with and the single characteristic that ties both groups firmly into their grouping is Personal Integrity. A good boss will believe what they are saying (or will say nothing) and will be honest about what they are passing up or down. A bad boss will try to tell everyone what: (a) makes the boss seem to look good; and (b) what the boss perceives the person wants to hear.
A good boss also must be a politician, must be decisive, and must be able to balance a need for deliberation against a need for "good enough" answers, but if neither staff nor top management can believe them they won't be effective.
I've never had a boss that could do my job and I've rarely had a subordinate whose job I could easily step into. If the Engineering Manager is worth their salt then their staff will do technical presentations, not them so where is the overwhelming need for engineering experience?
David