Setting/changing 'Additional Info' on Products with code - is it possible?

Both the updateProductFields( ) and the createProduct( ) functions take a productInfo object as their parameter but it only contains options to change a subset of a Product’s features. There appears to be no way to change some things such as ‘Additional Info’ using code, only by manually going into the gui interface. Is this true or am I missing something? Seems like a strange oversight seeing as they’re as fundamental as a ‘Description’ to adding Products.