But many (most?) counties have already digitized recorded deeds, at least by index... so it's just a matter of logging into the clerk's system and searching for

But many (most?) counties have already digitized recorded deeds, at least by index... so it's just a matter of logging into the clerk's system and searching for the situs address or APN or whatever's handy and you get the deed history, out of a good old fashioned relational database. How does blockchain improve on that?