With the remarkable success of their stormtrooper units near the back end of the war if the German leadership had taken a more proactive approach to military strategy would they have been able to break the trench stalemate in 1917 or even 1916 at Verdun?
They did use assault detachments at Verdun, including the elite flammenwerfer troops. The French front cracked wide open, but because of the realities of exploitation in WW1 the gap was closed.
Both sides could reliably breach each others' front by 1917, but the problem was exploitation. Neither side ever solved the problem of being able to advance quicker than an opponent could retreat or reinforce. In 1918 the Allies only were able to advance on a wide front because they outnumbered the Germans 2.5 to 1 in a manpower and much more in everything else. Plus the German army gave up and either deserted or retreated. It was beaten by the time the Allies went on their 100 days offensive, but even then the Germans were still able to fight effectively while the majority of units were deserting or just going home.
Technology just won't allow for a quick end to the war in WW1. Attrition was key. One side or the other needed to be ground down enough to allow the other to put them in a position to allow for peace. Even the German victories in 1918 were predicated on attrition creating weaknesses in the Allied lines that could be exploited.