I read it alongside "The Arms of Krupp"[1], and found the combination highly synergistic. The sensation of perspective is multiplied further if read with "All Quiet on the Western Front".
[0] https://archive.org/details/overtopbyamerica00empe
[1] https://openlibrary.org/books/OL24200511M/The_arms_of_Krupp_...
Besides other interesting things, it contains a ton of evidence cited from soldier letters.
"The Face of Battle is military history from the battlefield: a look at the direct experience of individuals at 'the point of maximum danger'. It examines the physical conditions of fighting, the particular emotions and behaviour generated by battle, as well as the motives that impel soldiers to stand and fight rather than run away."
http://www.goodreads.com/book/show/275833.The_Face_of_Battle
It is available free as a Kindle ebook: https://www.amazon.com/Over-Top-Arthur-Guy-Empey-ebook/dp/B0... (some reviews can be found here: http://www.goodreads.com/book/show/1517707.Over_The_Top)
Empey was an American who managed to get in the mix with the British soldiers before America entered the war. His account is based entirely on his own first-hand experiences. His last patrol depicts an utterly futile foray at night in which dozens of his comrades lost their lives and he (and I believe one another) survived. I am going from memory here on something I read quite a while back and so my summary may be imprecise. But anyone wanting to get a sense of the horrors of what it meant to fight in such battles will most certainly get it through this account.
The strange thing is that this became a runaway bestseller in America in 1917 and 1918. Far from recoiling at the horrors, the public chose to celebrate the heroism of the soldiers who put themselves in such incredible danger.
It is in any case a bone-chilling account to read this and all the more so because its style is almost detached and matter-of-fact, even clinical in describing one horror after another.