I could not understand how anyone missed how Superman looked at Lois before he zoomed out the window and then her reaction.
I always really enjoy BGDF. But, yes, this is the one where the logic of it falls down for me. They must have been blind as a bat not to notice. And what annoys me especially about that scene is that they could have so easily done the big farewell somewhere private - at Lois's apartment, or in Smallville, say - and avoided the problem in the first place. Setting it at the Planet was just dumb.
LabRat