"As the ET that conducts the hearing is bound to ensure that the case is clearly and efficiently presented, it is not required to stick slavishly to the list of issues agreed where to do so would impair the discharge of its core duty to hear and determine the case in accordance with the law and the evidence: see Price v. Surrey CC Appeal NoUKEAT/0450/10/SM (27 October 2011 ) at [23]."