I used to work at a bank. I joke to my friends that if you ever see their code base, you wouldn't leave your money with them.
*AFAICT, each keystroke has to be sent to Redwood City to be individually massaged and returned.
It's not as bad as you think. That's essentially how SSH works for instance, every keystroke has to be sent to the server before it shows up.
I remember waiting multiple minutes on a production system on more than 1 occasion! =D
Is it an older terminal-based system? Lots of those were designed (and still in use, 40+ years later). Usually it's not a big deal, in fact faster than modern interfaces, because they're built for decades-old hardware and low baud rates. Of course if you're still running the original hardware or have really screwed things up then performance goes out the window.