I would have addressed him directly, I think the most likely result would have been an apology, sincere or not. But I’d always have that in my back pocket to use if needed.

Southern Bell was a large enough company that firings are pretty rare without cause or due process. My performance would have protected me for a while, time enough to find a new job if needed. If I felt any sense of retaliation for me having overheard him, I could file a lawsuit. Much would depend on his reaction and response but I’d speak up.