I feel with the correct training there is no reason why the engineers can not run the aircraft. Is quite common practice in the fixed wing industry.
But fixed wings aren't flying until they're doing a rate of knots. A helicopter can be damaged very easily during a rotors turning ground run by a poorly managed cyclic position, let alone by getting airborne and losing control of it.
But if someone else gets trained up to do it so I don't have to go in on a day off or midnight (done both a lot more than once), I'd be more than happy. Provided they didn't knock the hell out of the droop stops or chop the tail off in the process.
