If a woodcock is shot at 15 or 20 yards there is not one that could fly through the pattern of a cylinder bore gun using 7/8 or 1 ounce of 7 or 7 1/2. But the larger shot might make a mess if the pattern was centered. Maybe that is the reason puny 9’s are commonly used—less damage to the bird. Can’t think of another reason. (Oh, I’ve never even seen a woodcock, so guess I’m an armchair expert).

When an old man dies a library burns to the ground. (Old African proverb)