Betty (or Betsy) Ross was a supporting character from the very early Cap stories. Some have identified her as the agent who pulled her old-maid mask off at Erskine's lab, although I'm not sure on what authority (the Adventures of Captain America modern limited series gave that woman a very different identity). More often she was associated with Camp Lehigh, either as a secretary, and aide, a morale officer, starring in the camp play, or whatever. At the time of their writing it was evident that Betty was not intended to know who Cap was, and she occasionally had a mild flirtation with Private Rogers (who got very embarrassed about it).
 
Now the speculation. Suppose Betty WAS the woman present at the super-soldier experiments. Suppose in fact that she was a very senior agent for the US government. Steve Rogers has just become the first and last product of the Erskine treatment, and he has been invested with a major role in both America's propaganda war and its counter-terrorist operations. It makes sense that the government are going to have somebody to keep tabs on him. They arrange for him to be posted at Camp Lehigh. They need somebody close to watch him. Betty? I'm with Toro on this one.
 
The idea that Betty Ross keeps close to subsequent Caps is also feasible if she has an assignment to do so. Beyond that, a lot depends on whether we assume that these replacements were really calling themselves Steve Rogers and Bucky Barnes or whether they were merely depicted as doing so in the (fictional) comics of the era. If it is the former, if they really believed themselves to be the genuine item (or at least the '50's Cap and Bucky did), then either they were the dangerous delusionals depicted by Engleheart, or somebody has a vested interest in preserving Steve Rogers' identity. And in either of the latter cases, Betty Ross is implicated right up to her yellow-and-green neck.
 
Let's really go way out now. Sometime later Betty Ross becomes Golden Girl and replaces Bucky as Cap's sidekick for the remainder of the '50's Cap's active duty. Bucky, shot by Lavender (as I remember, but correct me if I'm wrong), is last seen recovering in hospital and is never mentioned again! Does this Cap forget him, just as he has forgotten that he isn't the real Steve Rogers? And how does Golden Girl fortuitously develop occasional light-powers just when she needs them? 
 
So who is Betty Ross really? Is her name an in-joke pseudonym taken because of her assignment to stay close to Cap and ensure that there will always be a Captain America? Is she a mistress of disguise, a top espionage agent? Does she have a range of unrevealed powers, including the ability to fire light or energy bursts and to alter people's memories? Can it be that Makkari was not the only Eternal active in the war? IS BETTY SERSI??!
 
A few random Sersi points: (1) Her memory of her past life is far from complete; (2) She was fascinated by Captain America when he first called on her for help in a case, and spent quite a lot of time after that flirting with him to embarrass him - just as Betty did; (3) She has been involved with at least one other amnesiac hero, Gilgamesh (in the Citizen Kang storyline).
 
Well, there you have it. Is it possible? Could Sersi have been active during the War years in much the same way that Makkari has been revealed to have been? What fo you think?