In Dragonfly Falling, Collegium returning fire on the first night of the siege and destroying over three-quarters of the Vekken siege artillery is most definitely a CMOA. The entire volley was fired blind, aimed using only the calculations that Collegium's mathematicians had made earlier that day.Awesomeness by Analysis does not do it justice!
Actually, the whole siege is pretty awesome, considering that Collegium, with a force consisting only of scholars, artificers, statesmen, and a meager militia, managed to stand against the forces of an army composed of Ants, a culture centered around war.
Even better: In The Scarab Path, it is shown that the vekken cannot understand how could the military inferior Collegium resist their siege, and are thus terrified of them.
Tisamon's amazing death/ assassination of the Emperor in Salute the Dark.