During the Great War, some officers took to wearing similar jackets to the men, with the rank badges on the shoulder, as the cuff badges made them too conspicuous to snipers. This practice was frowned on outside the trenches but was given official sanction in 1917 as an optional alternative, being made permanent in 1920, when the cuff badges were abolished.
Interesting. I was led to believe the move to the cuff was because it was less conspicuous there than on the shoulder in the trenches.
I haven't seen a picture of a WW1 Officer with the rank anywhere but the cuff, but obviously that doesn't mean it was the only way.