Around here most of the design and build firms that do a reasonable amount of business have staff that know the codes and provide cheat sheets for any details that the construction crews need. And since most of the designs have "common" design solutions to code issues the crews gain experience by seeing the same design solutions time after time. This makes it easier for the designers, builders, and inspectors.
Smaller firms or firms that do a lot of one-off designs will always have difficulty. If the AHJ's office wants to have a better relationship with them, the AHJ's office could provide a list of code changes and what paperwork and construction changes are needed. No offense but if the AHJ's and inspectors who post here are asking code questions it seems a bit much to expect that contractors will understand the code.
Smaller firms or firms that do a lot of one-off designs will always have difficulty. If the AHJ's office wants to have a better relationship with them, the AHJ's office could provide a list of code changes and what paperwork and construction changes are needed. No offense but if the AHJ's and inspectors who post here are asking code questions it seems a bit much to expect that contractors will understand the code.