In the event, of course, the B-17s found it unsafe to bomb from 20,000
feet and moved up much higher.

And still, per the Germans, hurt them much worse than the RAF did.

Freeman relates in "Might Eighth War Diary" an anecdote where a B-17 box
climbed to almost 30,000 feet to get over the weather and still put 20% of its
bombs inside a circle of 1,000 foot radius.

Walt