Are we allowed to say why mentioned scenes
don't make us go ... WHAT?
I still would have expected an angrier reaction from Lois (maybe I've read to many fics).
You're probably right--too many fics.
(/me ducks) Seriously, in the show, Lois showed herself remarkably forgiving of Clark, so her reaction in WHALTTA is in character. In NeverEnding Battle, remember how she came to the Planet after Clark sent her on that wild Godzilla chase? She accepted that he had a reason for behaving as he did, even though they weren't friends at that time.
In Tempus Fugitive, she got mad after Tempus revealed Clark's secret in the most humiliating way possible (in the future, everyone wants to know "how dumb was she?"). But she understood why Clark had deceived her and forgave him even before they saw the results of Tempus's meddling (when he started fading).
The longest she stayed angry at Clark was when he broke up with her "for her own good" and left without even giving her a chance to discuss his decision. I always figured she was using her anger as a way to keep him at a distance while she was trying to figure out if she really could live with a man who made life-changing decisions for both of them without listening to her point of view.
Other than that, Lois continually showed herself to be very forgiving of Clark. She exploded easily, but she didn't hang on to her anger--not with him. Because of that, her behavior in WHALTTA seemed very in character to me.