(b) In each county during the reappraisal function, the tax commissioner shall designate a tax department employee as the coordinator of reappraisal functions among the commissioner's personnel, the commissioner's designated agents, and the assessor's personnel so as to ensure that the resulting appraisal shall be complete, equal and uniform. In each county, the tax commissioner or his designated agent shall prepare a description of the number, job description and minimum qualifications of personnel needed to accomplish the reappraisal, other than permanent employees of the tax commissioner or employees of the assessor. The tax commissioner or his designated agent shall employ qualified individuals to fill the positions giving first preference to persons registered with the bureau of employment programs' job service program, but all such persons shall be residents of the county, or if the tax commissioner finds it necessary for efficiency, any contiguous county, or if none be available, the state. The tax commissioner shall make reasonable efforts to assure that the additional employment required by this article is allocated equitably among the several counties, with attention to the level of unemployment in and the population of each county.
(c) To the extent that the tax commissioner concludes that assessors and local employees have overemphasized or underemphasized local aspects in determining value, the tax commissioner may revise information concerning such values so as to achieve uniformity in the statewide reappraisal: Provided, That in any hearings or appeals under the provisions of this article the assessor or employee who participated in the gathering of such information may be a competent witness as to how tentative values were arrived at in the process of reappraisal before any such revision.