Aye, but they've been entirely logical all through. Peace with Russia/Germany/Italy early, and a discussed dividing of the Balkans with the Turks. Then an adroit backstab against Italy, and now, when circumstances demand it...another backstab against Russia. All perfectly executed, and easily seen as the next logical move.
Austria has the admirable capability in this game of only fighting where it could realistically hold onto its gains. It has been a very instructive experience contrasting Austria's leadership with the over-reach of the Roman emperor, the lap-dog submissiveness of the Ottoman Emperor, and the manic moves of the Russian Tsar. Truly slow and steady wins the race.