...After take off with engine failure it's practical reality to retract flaps, especially when heavy and fuel dumping is required, which could take up to 50 minutes [B74]. In many cities, as FRA, for example, you couldn't dump just anywhere, you'd be vectored up to the North Sea for dump. And besides all that, it's not a "distraction" to retract flaps, just as it is not a distraction to raise the gear after positive climb. . . with or without an engine failure.
