I am working on a wordpress site customization, my concern is if i remember correctly wordpress update happens in forms of diff's now so that only lines which are changed will be updated in the new instance. Is my understanding correct.
also is it possible to obtain these diff's directly without downloading whole package.
the reason for asking this is as most of you would have guessed as per requirements I am heavily customizing core files and some variables. that is strictly for internal usage hence can't contribute back at this time. however the upgrade issues is what i needed help from the community.