NEWMARKET, UK--On both sides of the Atlantic, the yearling sector in 2021 has shown an especially heartening vigour in the middle market--and you can't get much closer to its centre of gravity, on this side of the water, than Book 2 of the October Yearling Sale at Tattersalls. Despite losing the stimulus of Shadwell, which last year corralled 36 lots from this auction for 5,327,000gns, Wednesday's third and final session rounded off a quite astonishing performance overall. Never mind its giddy elevation on last year's sale, which had itself rallied...