Originally Posted by Northwest Airlines 1974 727 Accident
Because the use of attitude references is a fundamental of instrument flying which is stressed in Northwest's flightcrew training program, the Safety Board concludes that the flightcrew improperly relied on airspeed indications as a means of determining aircraft performance.
Back to the importance of a scan including attitude rather than airspeed when in any doubt of a/s.
A clear AoA display is another thing - some have suggested here that it is probably yet to be accepted as primary display data