When did Cat ... ?

"You always have good intentions, but you can go way overboard sometimes."
The nice thing about having long-time friends is that they are willing to bring some things to your attention that others don't, or won't.
One of my many such friends watches more of the various CW shows than I do, and visits some of the fan sites too, although she doesn't do any postings on them. However, she does find my postings on this site's Forum interesting and she usually agrees with me maybe a little more than half the time. But not this time.
We have played "the devil's advocate" with each other many times over the years, and that works for me because I enjoy hearing other people's ideas about things because they force me to re-examine and justify my own ideas and opinions.
However, she has recently pointed out to me that, while this works well enough with good friends, this approach doesn't always work with strangers. When I pointed out that I 'know' many of the people who also post on the Forum, she countered by saying that recognizing their 'non de plumes' isn't the same as knowing them personally. We talked about many things, but the above "quote" and the other comments are all that's really relevant to my recent postings.
And, after reflecting on what she said, I realized that she is completely right. I have taken something that I am very comfortable doing with close friends and used it on the Forum many times, and that has been presumptuous on my part, and very unfair to each of you. None of my contributions to any topic on The Forum has ever been done with the intention of putting anyone off, or of wanting to make anyone feel as if their opinion isn't important, because they all are; but my conversation with "A" has made me realize that this is what I may have done.
This humble apology to all of you is my idea, not hers, but I am thankful that the motivation for my doing so is, rather ironically, because of her playing 'the devil's advocate' for me. And I hope that anyone who may have felt less appreciated will realize how very sorry I am if I have given you that impression.
And now, if you'll all excuse me, I'll just go and sit in a corner for a little while.

Maybe I had better state my own position (or opinion) on this a little more clearly. No, I never felt that anyone working at CatCo or living in National City would be able to figure out that Kara = Supergirl. Cat was Kara's boss, and Kara was her assistant. So Cat was in a special situation; she had the opportunity to see Kara close-up on a daily basis. Other people working at CatCo wouldn't have been there during the Cat and Kara one-to-one situations (like when Livewire was in Cat's office). I can easily believe that Cat would have enough information (from direct observation) to come to the conclusion that Kara = Supergirl. But I wouldn't expect a rank-and-file reporter or features writer at CatCo to do so. (And certainly not an average inhabitant of National City).
Similarly, I wouldn't have any problem accepting that Perry White has figured out that Clark Kent = Superman. Sure, he may know, but doesn't care, as long as Clark's gets his reporter's job done on schedule. So he just keeps that knowledge to himself. And there may be the same sort of situation going on with Batman and Commissioner Gordon. I could easily accept that, too.
Also, I don't visualize Cat thinking "A-ha, that's it!", as soon as she heard about J'onn shape-shifting at the end of the "Falling" episode. No, I don't believe it would have been that kind of "Sherlock Holmes moment". I would rather expect that Cat slowly began putting all the pieces together at that point. It may have taken several days for her to finally come to the conclusion that Kara does in fact = Supergirl. I would expect her thought process to go something like this: "Wow - so there's an alien in National City who has the ability to shape-shift. Now that's interesting! I wonder if........ Yes, I'll bet that's what it was. So that's how Kara did it, how she pulled off that stunt in my office that night! Yes, that makes sense - more so than anything else I might have been thinking of."