That was a very big deal at the time. The A320 had just entered service, and was precisely the sort of publicity they didn't need. There's a few
discrepancies between the flight officers' accounts and the FDR, but I'm still inclined to say he just put power on too late after dropping below the
intended altitude. Takes time for a jet engine to spool up.
Something about the flight computer not reacting to throttle inputs was pilots defence wasnt it?
That was about the time people were starting to can Airbus software and programming off memory.