.  They were very successful against the Czars army. Like you say though they bled heavily in France and Belgium. All this of course led to various military thinkers to devise new ways of conducting warfare... the culmination being German blitzkreig, from then on it was catch up for the Allies  Not really. The Germans were late to the party. Liddell Hart & Fuller in the UK and a group of Russian officers led by Frunze, Tukhachevsky and Triandafillov got there first. German officers borrowed heavily from them, in the case of the Russians as a result of close contact in the 00s & early 00s