I've narrowed down this term's list to two choices. Essentially they come down too (in my mind at least) did "espirt de corps" matter and an analysis of the brigade commanders role.
I'd pretty much decided on the later gathered a few books and the first one I read was an interesting book, The Great War diaries of Brigadier Alexander Johnston edited by Edwin Astill. Following Johnston from a regimental officer via Brigade staff to command as per title, I was struck by the amount of pride Johnston had in his regiment.
This pride can be seen in its sharpest detail in his views of any other unit, with a particularly dim view of a Cheshire battalion in his brigade. Jump forward and when Johnston is given command of a battalion it's..yes the Cheshire battalion! But, in time he becomes (rightly) proud of this battalion- which makes me wonder if "espirt de corps" does matter. Oh dear, back were I started.