Rabbi Finkel from Mir would give Smicha as follows. He would randomnly take out one of the volumes of Shulchan Aruch (any section)and randomly open the page - and show it to the testee. He would then close the book and make the testee discuss the complete page - with all the commentaries on that page.
Are there any official accountings of this? Maybe some additional details on how this can be accomplished in Judaism? or how such a feat was achieved, practically?