Whenever this is discussed I always think of a bit in Robert Graves Great War memoir "Goodbye to all That". Graves was given a break from front line service and was training Canadian troops away from the front, and in parts this went right back to basics, including drill. When the Canadians complained along the lines of "Why do we have to do all this bull, we're not the Brigade of Guards?" ,Graves replied "When you can fight as well as the Guards, I'll go easy on the drill". he also noted that "smarter" regiments, such as the Guards, and his own regiment, The Royal Welsh Fusiliers, suffered far fewer losses from causes such as trench foot and other medical complaints. Being smart does not necessarily mean being efficient, but neither does being scruffy.
Re saluting, as far as I recall in most army regiments it was common practice among officers to salute only the colonel, and then only when first encountering him in the morning. Soldiers saluted officers at all times, of course, and quite rightly so
