I think we're thinking along the same lines on this.

What I've observed is that when there genuinelly is an excess of manpower, it's always down to management problems, be it a culture of "empire building" (managing more people makes a manager's CV look better and is a justification for higher pay plus some people just want to boss others) or trying to solve efficiency problems by throwing more "resources" at it (the whole mythical idea that more man-hours = more results) rather than understanding the process and improving it.

The very same management flaws that produce genuine situations of excess of manpower will also create all manner of somewhat related problems, such as environments of sistematic overwork and cutting down on personnel to given an appearence of "efficiency improvement". I would even say that these are all just different facets of the same way of doing things, were different market competition situations and/or the ups and downs of a company's life-cycle make each a different facet more likely.