Generally EMER DES is executed in a unnecessary hurry. EMER DES should be understood as two parts exercise. The EMERGENCY part and RAPID DESCENT part. Emergency is from possible hypoxia and this gets over when O2 mask is put on. In establishing communication one can definitely spend some seconds to ensure whatever it takes. Passenger masks have taken care of their O2 requirement. Now what is left is a rapid descent. Aircraft pitches down only at 1g, banks and turns at certain rate which doesn't increase no matter how fast one rotates the buttons. So just do it the way one does for normal descent except in select speed VMO/present speed and use speedbrakes. Rest is read and do.That's all there is to it.