"It is all too easy, even for an experienced ET, to slip into the substitution mindset. In conduct cases the claimant often comes to the ET with more evidence and with an understandable determination to clear his name and to prove to the ET that he is innocent of the charges made against him by his employer. He has lost his job in circumstances that may make it difficult for him to get another job. He may well gain the sympathy of the ET so that it is carried along the acquittal route and away from the real question- whether the employer acted fairly and reasonably in all the circumstances at the time of the dismissal."