Now, given the results in Jaeger (2010), it seems straightforward to assume that speakers also exploit this kind of variation in order to optimize the surprisal profiles of their utterances.
speakers are expected to prefer overt articles if they precede nouns with rather high surprisal, and to prefer article omission, if they precede nouns with rather low surprisal (in order to raise the surprisal on the noun and to distribute the information encoded more uniformly across the utterance).