I'm not sure anyone suggested this, but you only need to compare the files that the vb team modified from the last release. They usually post a list of what files/templates were changed from the last version, so, you only need to compare those files and update them. I'm about to try going from 2.2.9 to 2.3.0 like this and I'll let you guys know how it goes.
I'm pretty sure I'll screw something up.