I can see how you could tae a firm hold on a blackbird with one hand (hold the wings folded so it can't move about, and avoid the beak), lift the piecrust with the other hand, and pop the bird in the pie, whipping your hand out and closing the top in one swift movement. If you were quick, you could get another one or two in in the same manner, but how could you insert, say, number 17 without numbers 3, 8 and 11 escaping? Could a dozen synchronised sous-chefs simultaneously slip them in, while the boss pops on the top? (Sorry about the aliteration!)

Steve