"The exigencies of daily court room life are such that reasons for judgment will always be capable of having been better expressed. This is particularly true of an unreserved judgment such as the judge gave in this case … These reasons should be read on the assumption that, unless he has demonstrated the contrary, the judge knew how he should perform his functions and which matters he should take into account. This is particularly true when the matters in question are so well known as those specified in section 25(2) [of theMatrimonial Causes Act 1973 ]. An appellate court should resist the temptation to subvert the principle that they should not substitute their own discretion for that of the judge by a narrow textual analysis which enables them to claim that he misdirected himself."
“If I may quote what I said in Biogen Inc v Medeva Plc[1997] RPC 1 , 45: ‘... [S]pecific findings of fact, even by the most meticulous judge, are inherently an incomplete statement of the impression which was made upon him by the primary evidence. His expressed findings are always surrounded by a penumbra of imprecision as to emphasis, relative weight, minor qualification and nuance … of which time and language do not permit exact expression, but which may play an important part in the judge’s overall evaluation.’ … The exigencies of daily court room life are suchthat reasons for judgment will always be capable of having been better expressed.”
“21 But deciding the case as if at first instance is not the task assigned to this court or to the Inner House … Lord Reed summarised the relevant law in para 67 of his judgment in Henderson [Henderson v Foxworth Investments Ltd[2014] UKSC 41 ,[2014] 1 WLR 2600 ] in these terms: “It follows that, in the absence of some other identifiable error, such as (without attempting an exhaustive account) a material error of law, or the making of a critical finding of fact which has no basis in the evidence, or a demonstrable misunderstanding of relevant evidence, or a demonstrable failure to consider relevant evidence, an appellate court will interfere with the findings of fact made by a trial judge only if it is satisfied that his decision cannot reasonably be explained or justified.”
“(1) Where a question of fact has been tried by a judge without a jury, and there is no question of misdirection of himself by the judge, an appellate court which is disposed to come to a different conclusion on the printed evidence, should not do so unless it is satisfied that any advantage enjoyed by the trial judge by reason of having seen and heard the witnesses, could not be sufficient to explain or justify the trial judge’s conclusion; (2) The appellate court may take the view that, without having seen or heard the witnesses, it is not in a position to come to any satisfactory conclusion on the printed evidence; (3) The appellate court, either because the reasons given by the trial judge are not satisfactory, or because it unmistakably so appears from the evidence, may be satisfied that he has not taken proper advantage of his having seen and heard the witnesses, and the matter will then become at large for the appellate court.”