Well, Kingmambo's very best offspring have generally been milers, and Henry's full sister, Queen Cleopatra, was best at a mile, although she wasn't disgraced when tried over 10f.
Henry's 2-y-o career, highlighted by his Coventry Stakes win, is indicative of a horse whose main asset is speed rather than stamina. His style of running in the Guineas was not that of a horse who might fancy a longer trip.
His female line is a high class one, but has predominantly produced horses suited by distances of around mile or less, the best of them being the champion Silent Screen, who I think never won beyond a mile.