On the NG Boeing disconnects A/T. When I asked Boeing pilot he said it was to comply with Boeing's philosophy of manual flight = manual thrust. How pedantic is that? I suggested they had introduced a massive threat, and perhaps after the first RA followed by stick shaker they would be reviewing their procedure. There was little reaction, but a note was made. On your day, when you are at the sharp end wrestling with the bronco you may choose to use the depth of airmanship you have and do what is necessary rather than dither around.
Say you're in a LVLCHG descent, autothrottle commanding idle thrust, Flight Directors showing, say 8º down pitch for the descent - and a "TCAS Climb" event occurs. You disengage the autopilot and pitch up, away from the Flight Director command, and follow your pre-decided non SOP action of leaving the autothrottle engaged.
What does the autothrottle do? Does it remain in idle thrust, attempting to follow the valid Flight Director commands for the idle descent? Are you only hoping for the Alpha floor function to save your stall as you pitch up without adding power?