I'd almost swear I saw in a documentary on the Schweinfurt raid that the bombers kind of went out of their combat box right over the target area; and into some kind of amorphous "formation" as they proceeded to bomb; then went back into their combat-box on their way out.
No, the Schweinfurt raid followed the normal tactics. Here's a photograph of some aircraft of the 306th BG over Schweinfurt on 14th October 1943, maintaining their formation in very heavy flak. This Group lost 10 aircraft on the raid.
I have never read an account which mentions the use of a different formation, nor that the German fighter or flak defences succeeded in breaking up the formations.
Just 88 of the 1,222 bombs dropped actually fell on the five plants attacked. The largest plant (Kugelfischer) suffered a limited loss of production for a six week period.
This for the loss of 60 B-17s and 600 men, another 142 fortresses returned with various degrees of damage, 5 crashed in England and another 12 were destroyed in crash landings at their airfield or were written off. 121 of the damaged bombers eventually returned to service. Another 5 fatalities and 43 wounded airmen were recovered from the returning bombers.
On the positive side, American gunners claimed 186 Luftwaffe aircraft as destroyed. The Luftwaffe in fact lost 38 aircraft shot down (eventually another 21 seem to have been written off or 'recycled') of the 670+ that made contact with the US formations, losing 29 pilots KIA or MIA and another 20 WIA.
In four full strength missions in seven days in October '43 (Bremen, Marienburg, Munster and Schweinfurt) the 8th Air Force lost 148 bombers, 50% of its daily average operational strength. This was the final nail in the doctrine of unescorted day time bombing, but at what a cost.
Cheers
Steve