Pam, I wouldn't add anything at all in - this is just perfect as it is. I have no trouble working out why Lois came in disguise, or why Clark didn't recognise her, or how Clark figures it out, or where they go from there. I think any explanations added in would take away from the sweetness of the story just as it is - and also run close to patronising your readers, who are well capable of working it out for themselves.
Just my (Can) 0.02c worth!
Wendy
