I believe the traditionally-suggested thing involves labeling such imports so that their source is apparent and clear (like an "(imported from file) (?)" note), thus allowing anyone who saw it to make up their own mind about how much trust to put in the words as published, complete with nice prominent FAQ link about what exactly "imported from file" meant and implied, for those who did not already know on their own.

Not sure how much that would be wp-beans to people in possession of files to import from, however. Oh well.