Indeed so, the book (which I've just read, and which is excellent
) states that there was a deliberate plan to drop the bombs at an angle of about 35 degrees to the runway orientation. That was clearly achieved from the graphics shown here.
The thinking was that this would ensure that at least one or two bombs would actually hit the runway (as opposed to a run straight along it, where there was more chance all 20-odd could miss the 45 yard wide runway to one side or the other).
When I last visited the Islands (6 years ago now), there were still plenty of big crater-like holes around the Western end of the airfield - that was 18 years after Black Buck.