I don't understand how some of the parents decided not to separate the twins. I found it very unsettling to see the adult twins still joined. Surely they cannot have a normalish life?
I was thinking about it myself, when I read the link. I think the problem is, that you know you might lose one or both babies. It's always a huge risk. Often, they are safer together- it's just society finds it hard.
There are a lot of examples, I might need to look up actually... but Abbey and Brittany Henson for one. Would not have survived a separation, but seem perfectly well together. And lots of others separated, where one or both have died.
I don't find it upsetting either. People are different- it's so interesting. It's amazing and telling, how well people can adapt, and have great lives, without others seeing them as "normal".