the real problem was that even with twice the subs..you still only had the same amount of targets and for the first two years america was neutral and supposedly not targets.
course..after america entered the war with the fact that germany was twice as active..would have only speeded up the efforts to fight the subs.
My opinion: no , not in the long run
If we should have to fight, we should be prepared to do so from the neck up instead of from the neck down. General James H. Doolittle, USAAF