When using the nomograph for calculating the amount of priming sugar in Classic Styles and How to Brew, it refers to the temperature of the beer. Is this the ambient temp that you are priming at, or is it the projected temp that you will be serving the beer at?
The assumption is the beer is saturated with CO2 at it's current temperature. If you have cold crashed the beer, it's going to have more CO2 in solution than if it is at room temperature.