No one will ever truly know what the results would have been had BC not been used the way it was because we cannot go back and relive history. Its all just a matter of speculation, sixty years after the fact. Of course it is also fair game to speculate on what would have happened had BC not engaged in a total war effort. Im certain that we can all agree that the offensive did have some impact on the industrial capacity of Germany to wage war on multiple fronts.
Sure, production might have went up until the crucial year of 1944, but as Ken pointed out, how much greater would that capacity have been had it not been for BC? Yes, the cost of material and men to the Allied cause was great; bomber crews suffered the highest per capita casualty rate of any branch of the allied forces. But obviously given the ultimate outcome of the war, it was a cost that we could bear and it was a cost that had to be paid for ultimate victory. How much longer would the war have lasted without BC? Would we have been successful on D-Day? Would D-Day have even happened in 1944? How many more allied lives would have been lost in the invasion? How many more Dutch civilians would have starved to death had the war lasted a couple more years? How many more slave labourers would have died in the service of the Reich? How many more Jews would have been cleansed? I could go on and on, but Ill leave you with one final thought. Would an additional year or two have allowed Germany to become nuclear capable?