I can't post verbatim what happened because I can't quite remember the setup that they guy flying had the plane in, but in short, he messed up. If I remeber what I was told in initial training correctly, he was a pretty inexperienced in the Bus. Like any computer, garbage in = garbage out.
I can tell you this, I've been very pleasantly surprised at how much I enjoy flying the 320. Yes, the computer sometimes has a hard time making crossing restrictions and the French/Honeywell seemed to not mind target +/- a bunch, but if you just mind the shop and do some pilotage intervention, it's not a problem. Of course you have to remember that it is late 1980's technology. From a comfort standpoint, they hit the ball out of the park. I don't miss the yoke one bit, the table is great, and I can fly 6+ hours and not have my but killing me when I get there.
This accident gave it an undeserving bad rap.