Joel, thank you so much for directing me to your narrative, "My First BillG Review." It seems plausible that Lotus may have been the historical origin of the flaw that troubled me. You may think me "anal," but cheating on the leap-year algorithm to save memory seems to me to be irresponsible. I've been retired for more than 20 years so I'm aware that I'm out of touch with current practices. Back in the mid 1960's I was into biomedical computing which included in the early 1970s some systems for critical care of patients. Our computers (the LINC and its derivatives) initially had 1K of 12-bit magnetic-core memory. When they were expanded to 2K we wondered what we'd do with all that memory. Yes, memory was at a premium, but as lives depended on it, the highest priority was on exact and reliable correctness of the assembly-language programs without compromise. Hence my mindset.

You report the suggestion that an intentional bug is not really a bug. For me, an intentional bug is the worst kind, an unconscionable bug. I had imagined that what seems to be perpetuated sloppiness would have been fixed by now. It was Laurence J. Peter who observed, "Computers magnify the confusion of their users." Maybe that should be modified to ...magnify and perpetuate... So ends my rant. As a result of your response I now regard my questions as "solved." Thank you.