I recently came across the reversi go page. I had edited this page in the past but I couldn't understand what I was saying. The diagrams didn't make any sense.
Looking at the page source it became obvious. The diagrams were supposed to have multiple stones numbered the same way. But only bottom right most one was numbered. So at some point this functionality was broken. I don't know how many pages this affects but it can make diagrams completely incomprehensible.
This is not a bug. Every diagram on SL, when clicked, can be be downloaded as an SGF file. If a diagram were allowed to have multiple stones with , , etc, there would be no way to generate an SGF file that makes sense.
To do what you want, you could use and and a comment like: "In each corner black followed by white results in death for the corner."
It might not be a bug, but it used to be possible. I didn't see the change posted on wikinews. It might be hard tracking everything down. I'll change the reversi go page tomorrow.
It used to be possible and a refactoring of the code some months ago removed the possibility. As I like the idea of having a 1:1 relationship between the diagram text and the produced diagram graphic, I have fixed this unintended change. If a diagram has moves with the same move number, then no SGF is created.
Thanks for the report.