The real demon here: ambition.
There are those with more ambition that skills (and I refuse to consider ambition as a skill in itself even though I am ambitious at times). These are the dangerous ones. They will blame others, deceive, coerce and drop people in it at a drop of a hat.
The best managers I have worked for felt more like coordinators. That isn't all they did but they felt that a softly, softly less intrusive approach was most effective. They were all good umbrella holders to a man (in the original non-gender specific sense).
For those of you not getting the umbrella holder reference, imagine a fan spraying some substance out. You and your colleagues are in front of the fan doing a difficult task. However, between you and the fan is a person with an umbrella. The umbrella holder is not trying to keep the substance off of themselves. They are keeping you and your colleagues free from the distraction of being hit by the aforementioned substance. Umbrella Holder = Great team player. They rock.
-- Stop your grinnin' and drop your linen...they're everywhere!!!