The Fifth Army plan was more ambitious than the plans devised by Rawlinson and Plumer, which had involved an advance of on the first day, by compressing their first three attacks into one day instead of three. Major-General John Davidson, Director of Operations at GHQ, wrote in a memorandum that there was "ambiguity as to what was meant by a step-by-step attack with limited objectives" and suggested reverting to a advance on the first day to increase the concentration of British artillery. Gough stressed the need to plan to exploit opportunities to take ground left temporarily undefended, more likely in the first attack, which would have the benefit of long preparation. This had not been done in earlier battles and vacant ground, there for the taking, had been re-occupied by the Germans. At the end of June, Haig added a division to II Corps (Lieutenant-General Claud Jacob) from the Second Army and next day, after meeting with Gough and General Herbert Plumer, the Second Army commander, Haig endorsed the Fifth Army plan.