You are correct Hellshade.
Formation keeping was considered "life" for the two-seater crews by all accounts I have ever read.
If a machine dropped out of formation due to damage it was GENERALLY on its own. Sometimes the formation would try to swing back (sometimes!) and pick up depending on enemy strength and will or a hard-charger would break formation and go back to help a friend but this was generally frowned upon. The safety of the group was what mattered. A 4 plane formation is 10 times as strong as 4 individual aircraft. Everyone knew that and tried to keep up and stay in formation. I have seen multiple combat reports where is is said that "Captain X and Lt. Y were last seen dropping back due to presumed engine trouble" and that was the last they were seen. This was a accepted fact of life. The break up of the formation is what the attackers always strived for (and I have some MvR quotes to prove it) and the crewed machines tried to avoid.