Hi Philip,
I confess to not being much of a Bach scholar, but I believe that you performed the "Aria" quite well. The memory slip or other minor fluff was unimportant because you maintained both continuity and musicality. Plus Bach's music has an improvisatory character to it anyway. In your facial expression, just look cool. Except for a small few who really know the music, the large majority will not suspect that anything went awry. I strongly believe that we all tend to magnify flaws in our performances or recordings. I know I do! (I'm my worst critic for sure.) On listening to one of my own recordings, I'll avert my ears as the dreadful error approaches, and tune it totally out. Then a day arrives where I tell myself that my ears are to remain wide open--and a revelation! The problem is hardly perceptible!
Another thing: Today we get so used to hearing highly edited and sanitized CDs "performed" not by artists, but by recording engineers, that we believe we must likewise achieve that supposed "perfection". We should certainly strive for perfection in performance, but being mere mortals, seldom we might come close but will never actually attain it. Horowitz used to say that if a person played a piece countless times and managed to approach perfection just once in a lifetime, then that was a very fortunate pianist indeed! My feeling too is that if the audience hears a slip here or there, it reveals the edge of the pianist's titanic struggle with the forces of the music, which adds greatly to the audience's excitement and appreciation. I recall seeing Rubinstein at Symphony Hall in Boston. He made occasional mistakes, but the audience could care less, as they were mesmerized by his true artistry.
Again, fine playing!
David