"21. … It is not the task of the EAT to decide what result is 'right' on the merits. That decision is for the ET, the industrial jury. The EAT's function is (and is only) to see that the ET's decisions are lawfully made. If therefore the EAT detects a legal error by the ET, it must send the case back unless (a) it concludes that the error cannot have affected the result, for in that case the error will have been immaterial and the result as lawful as if it had not been made; or (b) without the error the result would have been different, but the EAT is able to conclude what it must have been. In neither case is the EAT to make any factual assessment for itself, nor make any judgment of its own as to the merits of the case; the result must flow from findings made by the ET, supplemented (if at all) only by undisputed or indisputable facts. Otherwise, there must be a remittal."
"The disadvantages of this ruling can be mitigated to some extent if the EAT always considers carefully whether the case is indeed one where more than one answer is reasonably possible... even where more than one outcome is indeed possible, there is in my view no reason why the EAT cannot still decide the issue if the parties agree; and in an appropriate case they should be strongly encouraged to do so."