"terroris(ing) those under him to the extent that they are afraid to express their opinions for fear of being (sacked)" (Haldane Diary 31 March). Allenby was annoyed at the apparent favouritism shown to Gough at Army Commanders' conferences. Gough was allowed to expand Fifth Army's role in Arras beyond what had originally been intended. Gough commanded the southern part of the offensive (Horne's First Army attacked in the north, including the famous Canadian attack on Vimy Ridge, while the main attack was conducted by Allenby's Third Army in the centre). 4th Cavalry Division was allotted to Gough's sector to exploit any breakthrough achieved. Building on his experiences on the Aisne in September 1914, Gough formed mixed brigades of infantry, cavalry, artillery and engineers during the German withdrawal to the Hindenburg Line in mid March. 2–9 April saw costly fighting on the outskirts of the Hindenburg Line. Over the protests of the ANZAC Commanders Gough launched an attack at (First) Bullecourt (10–11 April), described by Sheffield as "hasty, ill-prepared and ultimately disastrous" ... "the infantry plan was disrupted at a late stage by Gough's ill-fated employment of tanks". 4th Australian Brigade lost three-quarters of their men in action, 12th Australian Brigade half of each battalion engaged. Simkins writes that "(Haig) yet again indulged Gough's tendency to launch precipitate and ill-considered attacks", while Prior & Wilson describe the attack as "singularly barren". Bullecourt became known as the "Blood Tub". Gough was ordered (Haig diary 14 April) to prepare to "pierce" the Hindenburg Line "astride the Bapaume–Cambrai Road" if Allenby's main attack made sufficient progress. Gough attended an Army commanders' conference on 16 April. With the Arras offensive bogging down, he later declined to conduct further infantry attacks as part of the 23 April push, restricting his efforts to artillery only. At the Army Commanders' Conference on 30 April 1917 Haig, who had just been told that Nivelle was to be sacked, still expected Italian and (contrary to the War Office view) Russian offensives to take place that year. He told the Army commanders that he was not entirely clear what the BEF would be doing for the rest of the year but that he wanted to "shift the centre of gravity up to the Second Army". In the afternoon after the conference he told Gough that he was to command the proposed Flanders Offensive, and ordered him to speak to Colonel Macmullen