You know that some crazy (fully grown) individual would do it someday..I did 
I wanted to see how close the sound could be kept to the original profile and what was goin' on noise wise
I did it both ways (black to white and then white to black)..and didn"t get anything grey .. This helped eliminate any possible problem..of course starting with the same rig..I didn't copy the copy ,-)
The result is what you expect..not much difference ..it confirmed to me that a little hiss is added ...you will only hear it on high gain rigs..the higher the original is gainy and noisy the more you'll hear it
It is probably not much mentionning..I think it's equal or less than a jump of 1 green led..this is expected ..nothing can be placed in front of high gain and be 100% silent..it is just not possible
One thing I wish was more silent is the added hiss while profiling..it can be high on really high gain tones..it come from the signal generator and goes away once you start saving the rig
I also wanted to make DI profiles of the two heads that were there..and something funny happened..check it in the trouble shooting section 
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