Possibly a case could be made for a (relatively) cheap / simple single to teach basic rotary handling including wariness of downwind ops, limited power margins etc.
Sioux/Whirlwind
Gazelle/Wessex
Squirrel/Griffin
Case made??
To be serious for a moment, there were always (and probably always will be) a few basic rotary students who couldn't fly rotary - even some experienced FW pilots. The cheap(er) simpler type found these out early, while the "advanced" type - latterly with 2 engines - was good for the applied stuff and for teaching the "freight deck execs".
Seems simple
pour moi, but then no-one asked me........
