Charlie,
I wonder, please, if you would kindly take a look at Reply No. 7? I note that Lieutenant R.H. Tautz MC is referred to in the 4th Bn. Loyal North Lancs.' history as being wounded in action with that battalion on the 20th September 1917 whilst serving in the Ypres sector. It would seem that his Military Cross could have been in recognition of his bravery in that action in which the battalion incurred very heavy casualties. Later, as you say, he was attached to the 2nd Berkshires on the 17th April (1918).
Turning now to Lieutenant Edward Kerruish Moore who it appears was also posted to the 2nd Berks. on the 17th April, only to DOW on the 25th April 1918, I see that the CWGC have him down as being an officer in the 9th Manchesters. However, "Officers Died" have him recorded as an officer in the 8th battalion and his surname as Kerrnish.
The CWGC state that Moore is buried in Daours Communal Cemetery Extn. which is near Amiens, that is a goodly distance to move a casualty from the Chemin des Dames where the 2nd Berks. were in the line on the day in question. Do you think there is something adrift with the records? PhilipG.