Jude, what pain was Superman condemning himself to bear in Superman II? To me, the most painful thing about the entire movie was how extremely pleased Superman seemed to be at having wiped Lois's mind after having sex with her. That smirk on Christopher Reeve's face at the end of that movie told me that his Superman was as happy as could be that he had gotten away with sleeping with her without ever letting her know about it. Talk about using a woman! Talk about pulling the wool over her eyes! Talk about lying about yourself to her! I found him utterly disgusting.
I hated the mind wipe thing as much as anyone else, but I never interpreted the "smirk" on Christopher's face that way at all. To me it wasn't a case of him being secretly overjoyed that he'd gotten away with "a night in the sack" and wouldn't have to face any possible consequences. To me he was simply relieved that he had taken away Lois' severe emotional pain, and taken her back to the happy woman of just a few days ago.
Even though he didn't display it as overtly as she, I felt that both of them were suffering. They were in love, yet couldn't be together because he felt that his obligations as Superman had to take a higher priority. She acknowledged that, but that knowledge obviously didn't make her feel any better. And there was the truth that she might never meet anyone else who would live up to the standards of her "lost great love".
Now, since it had all just happened there was no denying that the emotional distress would be at its greatest point here, and certainly her pain would have lessened over time. So in that sense it would have been better for him to have waited before doing something, but that obviously wouldn't work for plot purposes.
Now if Clark could have implanted something in her brain to make her not forget, but to realize that she "never really loved" him in the first place, that would have been nicer, of course... But since Superman is the "real" person in the movies, that claim wouldn't go too far. Or she could have just realized that one night together was enough for her...
Anyway, probably this implanting stuff is beyond Superman's powers, and not the way that the movie people wanted to go.
The notion of choosing between Lois and "a greater good", although it cuts to the core of all the romantics out there, is hardly new or unheard of. And our own Clark did (misguidedly) choose to help NK and leave Lois behind, knowing that there was at least a possibility that he might never return.
Kathy