Hello Confusedcuda,
Short answer is that a variable PCV valve confuses the IAC. The IAC is constantly trying to compensate for the changing volume of air the variable PCV is introducing into the engine.
This translates into idle/cruse issues.
Install a fixed orifice and reset the the IAC as described in this vid.
Solving Holley Sniper High Idle Issues
You can also use the PCV1009DL fixed valve.....
Hope this helps...
Happy Mopar :)
Arron.