▁was ▁effective ▁in ▁subst itut ing ▁workers ▁of ▁less er ▁physical ▁fit ness ▁for ▁those ▁capable ▁of ▁military ▁service . ▁Con cess ions ▁to ▁organ ised ▁labour ▁were ▁valuable ▁in ▁retain ing ▁the ▁co - operation ▁of ▁the ▁un ions ▁during ▁the ▁un rest ▁of ▁ 1 9 1 7 . ▁ ▁The ▁German ▁army ▁had ▁reached ▁its ▁peak ▁of ▁man power ▁in ▁ 1 9 1 6 ▁and ▁the ▁H inden burg ▁Program me ▁had ▁been ▁intended ▁to ▁reduce ▁the ▁bur den ▁on ▁the ▁remaining ▁man power ▁by ▁subst itut ing ▁machines . ▁In ▁ 1 9 1 7 , ▁the ▁West he er ▁had ▁managed ▁to ▁with stand ▁the ▁attacks ▁of ▁the ▁French ▁and ▁the ▁British , ▁while ▁off ensive ▁operations ▁had ▁been ▁conducted ▁on ▁the ▁eastern ▁and ▁southern ▁front s . ▁The ▁coal ition ▁against ▁Germany ▁increased ▁its ▁output ▁of ▁war ▁mater iel ▁even ▁more ▁than ▁the ▁increase ▁of ▁the ▁H inden burg ▁Program me , ▁an ▁industrial ▁competition ▁that ▁Germany ▁could ▁not ▁win ; ▁the ▁programme ▁w ors ened ▁the ▁labour ▁short age ▁in ▁Germany . ▁The ▁theoretical ▁changes ▁in ▁German ▁def ensive ▁tact ics ▁had ▁greater ▁effect ▁than ▁the ▁increase ▁in ▁the ▁size ▁of ▁the ▁army ▁and ▁the ▁output ▁of ▁weapons . ▁British ▁attacks ▁in ▁ 1 9 1 7 ▁were ▁much ▁more ▁compet ent ▁than ▁those ▁of ▁ 1 9 1 6 ▁but ▁German ▁def ensive ▁methods ▁were ▁adapted ▁to ▁neg ate ▁the ▁effect ▁of ▁the ▁m aturing ▁of ▁the ▁British ▁Ex ped ition ary ▁Force ▁(