True, Dave, but maybe you and Genghis will agree that in this particular case - assuming 1G cruise flight at F370 and IAS 255 (about M 0.75 - 0.80) - the AoA is likely to be something between +2 and +3. In fact it may well approximate the Pitch attitude shown on the PFD/ADI and the flight-control display in question (+2.7).
Genghis, you will recall that we've had much discussion on the possible efficacy of providing airline pilots with an AoA gauge: initially on the serial AF447 threads, but more recently on a specific thread, the title of which escapes me at the moment...