“The result is that in my judgment this appeal has to be allowed however unfortunate I find that to be. It is tragic for the parties concerned because of the waste of costs thus far incurred. It is unfortunate for the judge who strove hard to manage the case and keep it within proportionate bounds. But a cardinal feature of our civil procedure is that a trial is conducted on oral evidence where matters are in dispute and the judge ought, therefore, to have acceded to the request to hear the witnesses that the Defendant wished to call”