Are Wisconsin public sector workers overcompensated?

Crooked Timber

via Are Wisconsin public sector workers overcompensated?.

It seems like the main point here is that on an education normalized basis, the public sector workers are undercompensated.  But doesn’t that still allow for overeducated workers being hired in the public sector?  In other words perhaps the public sector workers are paid a competitive wage for their abilities, but their abilities are being effectively used, and the public isn’t getting a marginal product equal to what they pay public employees.