In virtually all engine-out approach accidents ... by trying to meet very specific ... requirements  [training standards requiring  the upgrading-pilot  to slow to a speed very near a "published"  Vmc]  ... coping with performance deterioration,   asymmetric thrust was added   ... led to  loss of lateral-directional control. 

The insidious factor
is that none of the victims seemed to
 recognize how  close ... to loss of control,
 even upon the verge of losing it,
 and the loss occurred 
 within scant seconds  . . .