During my time as an RAF student (1978/9) and latterly as a QHI, our training was for every one to be to the ground. In fact, once the speed select (Whirlwind 10) or throttle (Gazelle) was retarded, it was prohibited to advance it again until on the ground. So, in effect they were for real.
As students on the Whirlwind we were required to do a whole sortie of solo engine off landings (IIRC, this was with a total of about 40 hours of the 110 hour course completed).