You need to retain a proper perspective about engine failure. It is not a common way of crashing a helicopter: just look at the stats.
My understanding of the design of the R22 is that the engine was derated to reduce the chance of failure further. It is true that the relatively low rotor inertia means that IF you had one, you need to respond quickly to maintain/recover RRPM. The other side of the coin is that once the lever is down, RRPM will recover quicker than a high inertia system.
If I was worried about flying with a low time pilot in an R22 (as a pax without a stick) it would not be his response to engine failure but so many other things.