Due diligence in mergers and acquisitions

We had a long discussion at work today about due diligence related to mergers and acquisitions. In our experience most of the due diligence is centred on the easily quantifiable and little on the less easily quantifiable e.g. behaviors around pay and reward, or attitudes to workforce development and training. However, when it comes to 'successful' merger or acquisition it is the less quantifiable stuff that is frequently the deciding factor in whether the merger or acquistion will deliver the promised value. So our challenge is to develop and apply rigor around making the qualitative organizational aspects quantifiable, and get these included in due diligence processes.