I still have yet to see how the TH fix could hinder performance or an open idle air control valve will improve it.
It's not like the engine suddenly ingests more air through the IAC.
Personally I have seen no difference in performance running either way. Matter of fact I did not even see an improvement in rev deceleration with it installed. Not that I had a problem with hang before.
Only with the 65mm TB did I experience some minor TH and used the TH fix to stop it (~1/8" hole) It actually showed noticable improvement once I needed to use it.
