The fact that German industrial productivity rose in 1943 isn't a sign of the futility of terror/strategic bombing. It's a sign of Germany's utter lack of economic planning from 1939-1942.

Think about this; until about the middle in the war, most of Germany's workers were still working on a single shift. The quality and quantity of consumer goods dropped by a very marginal amount until late in the war (which meant that military gear was being ignored). And, despite pleas and tears from Speer, women remained Germany's largest untapped labor force. Let's not forget about Germany's remarkable lack of centralization in the early war.

Speer's reforms did a lot. But he tirelessly complained about the effects of bombing on centralization and productivity.

We really should thank Adolf for the creation of the V2.