I was slightly surprised to see some people respond to mention of Lois knowing CK=SM as a break-through by saying "she knows in Smallville". My first reactions was "she doesn't know in Smallville at first", but after watching that clip it is clear that there is the similarity that Lois knows in Smallville before the Superhero becomes public.
I think though what it the break is not that Lois figures out, she has done that before in Lois and Clark and Smallville and even Superman II, but that she figures out without going through the phase of loving the hero and rejecting the man.
