These two sources are about Haig and the Battle of the Somme in some. Source D is still form the television show called 'Blackadder Goes Forth' which was about the First World War. Source E is a cartoon published in 1917.
The troops are one of the reasons for these sources to be about the war and Haig. They were made up of regular troops, like Blackadder, who were very cynical and knew that they were all going to die some time. There were also volunteers, who made up most of the British Army. These were like George in the Blackadder series, which were extremely enthusiastic and believed that the war would be over before Christmas. They were heads of Houses from public school who thought they could lead soldiers in the battles. Blackadder says that they are "going over the top." This was a common phrase in the trenches.
This meant that the soldiers were going to climb out of the trenches and charge towards No-Man's Land. The still actually mentions Haig in it. They say he was "about to make yet another giant effort to move his drinks cabinet closer to Berlin." This means that his tactics were old and pointless. The cartoon mentions that the generals are absent from the front line. This holds truth in it because Haig was 30 miles behind the front line in his house. That is also what Blackadder means when he says "his drinks cabinet". Haig is living well with his drinks and in his house. The caricatures of the Generals in the cartoon are very much like Haig too. They all have the same moustaches and look very pompous and overweight.
However, there are some reasons why these two sources could not be about Haig and the Battle of the Somme. There is no detail of the battle or Haig in any of the sources. They said nothing about the fact that it didn't work, or that 20,000 soldiers died on the first day and 40,000 were injured. They also said nothing about the dates, July - November 1916.
In conclusion, these sources could be of use to a historian studying Haig or the battle of the Somme. There are some good facts in these sources. Television sitcoms can be very accurate in some way. The makers study the subject to get as much truth as they can. Accuracy can be very funny. Cartoons are meant to show what is going on in the world with some humour added to it and with a hidden message.