If random mutations were the source of variation that Natural Selection operates on, then no control could be exerted on the rate of production of variation (and thus on the species evolutionary rate), since random mutations are unpredictable in time and space.
Well, that's not true. We observe in many species (yeasts, for instance) that the rate of mutogenesis increases under certain conditions of environmental stress. So, in fact, the rate of variation
can be controlled, simply by increasing or decreasing the cell's ability to mitigate chromosomal damage and copying error.
In addition to the questions I've outlined in previous posts, which you still have not addressed, I don't see why the "experimentor gene" in your model needs to be anything but the regular, guaranteed supply of genetic variation represented by random mutation. You've constructed a model that explains exactly as much as random mutation does, but introduces as-yet-undetected genes to do so. In other words your model fails the test of parsimony.
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