Not sure if there's any good 'official' link, but: it depends on what you need to replace (adding methods? changing methods? changing resources?). In 90% of th

Not sure if there's any good 'official' link, but: it depends on what you need to replace (adding methods? changing methods? changing resources?). In 90% of the cases it's much faster, maybe by cutting build+deploy time by 90%, just because you don't have to rerun the app. In 5% of the cases it's a bit more involved but still faster. In 5% of the cases it fails miserably and you spend 200% more time just stopping everything, doing a clean build, and deploying it again just to be sure.