I've looked at Arthur Watts Doyle and the Brompton connection grows stronger. Although he joined the Inniskillins in Jan 1888, by March 1888 he had transferred to the Royal Engineers who are based at the School of Military Engineering in Brompton. His records also show he married the widow of a SSM in the ASC in 1895, so there is a vague ASC connection too.
I also found this in the National Roll of the Great War:
DOYLE, A. J., Pte., R.A.S.C. (M.T.).
He volunteered in August, 1914, and served on both Western and Eastern Fronts. In France he was engaged on the transport of stores and ammunition to the trenches, and in Salonica drove a Staff car. He was invalided home on account of ill-health, and discharged in May 1916.
He holds the 1914 Star, General Service and Victory Medals.
43, Brenthurst Road, Willesden, N.W. 10 16379
I wonder if that's our man with a wrong initial?