I think this is a poor choice when travelling on a noisy and disruptive public transport system. But then that is mostly the time I have during a day to read so I didn't particularly have a choice and many non-fiction books have managed to hold my concentration a lot better in noisy atmospheres.
I would really enjoy ten or twenty pages and then read another 5 and just totally zone out and have to go back to try and re read what I had missed. I found myself daydreaming at times. Then I'd snap out of it and realize I'd not taken in anything from a chapter. Believe me I was tempted multiple times to give up, but I persevered and I did increase my knowledge of the First World War.
The whole premise of the book is essentially the argument that the general public think WW1 was a waste of time because they've seen things like Blackadder/read war poetry. When really it argues that the war saw the BEF become a tuned fighting force that won a series of battles towards the end of the war sending the German forces reeling. It counters the idea that Haig was totally inept as a commander and looks to dispel the opinion that commanders sacrificed the lives of young working people carelessly for little strategic gain.
I agreed with a lot of Sheffield's assessments and I think people in the UK should make more of an effort to learn about events that were huge for the country and base their opinions on strong, objective historical texts rather than on emotive films and television series.
I'd pick this up if you are really keen on WW1.