Readers with a NE (Hull area) based layout may be interested to know that the D95xxs seem to have frequently run in pairs. I've notes in May and August 1967 which show I saw D9539/41 (on tankers passingBotanic Gardens), D9543/44 at Hessle Quarry, D9512/16 (still with 87E shed plate) at King George Dock, D9543/49 at Alexandra Dock and D9533/3x and D9541/D95xx at Hessle yard. Also seen at Brough was D9547 on its own on a freight. In October another visit found D9505 shunting on its own at Brough and D9541/53 at Hessle yard. Finally I saw D9531 in York North yards on 31.12.68 out of use.
It would appear that they took over many of the duties of the WD 2-8-0s from Dairycoates shed. presumably the use of two locomotives was necessary for braking purposes on the steep gradients of some of the dock lines.