I am not sure I have seen the valve configuration you have described but if you are talking about tub or shower valves then perhaps the "exception" below applies?
From the 2006 IRC...
"P2722.2 Hot water. Fixture fittings and faucets that are supplied with both hot and cold water shall be installed and adjusted so that the left-hand side of the water temperature control represents the flow of hot water when facing the outlet.
Exception:
Shower and tub/shower mixing valves conforming to ASSE 1016 or CSA B125, where the water temperature control corresponds to the markings on the device."