I've done all that. It's part of the reason I can make a thread like this in the first place.
But from the first notes I played through the (Archetype Petrucci) plugin, that particular aspect of the fizz I'm hearing, wasn't/isn't there.
It also isn't there when I listen to Cooper Carter's demo videos of the JPIIC in the Axe III, using his Majesty. Which is odd. I'm using the same exact preset he's using, and I'm pretty sure he has said he didn't use any post-processing.
Edited to add: I'm pretty certain it has something to do with my hearing being more sensitive to highs at low volume, even if that doesn't explain why I notice a difference between using the Petrucci Rig preset in the Axe, vs. the other things I mentioned.