And although you state 20 out of 28 were serious, on who's assessment was this based. Have you the details of all cases? And therein lies my point. BA management believe they were serious. They may well have been serious, but without independent assessment how can those decisions be trusted.
But if you follow that ethos, EVERY SINGLE TIME British Airways puts someone into a disciplinary process, they'd have to get an outside and neutral party involved to actually make a final decision. It's not practical.