This topic comes up from time to time and I am just wondering what facts are being copied exact person for person. I can see a Census fact being one and a Residence fact being another but as personal facts being copied exact what are other users wishing to copy?
I would agree that there are very few cases where I would want to copy a fact and leave the new copy unchanged. For me, however, that would not be the point. I frequently copy and paste a few lines of computer code, for example, and then make a few minor changes in the newly pasted code. That would be the primary way I would want to copy RM's facts. Indeed, I virtually never create a new RM source from scratch. Instead, I copy an existing one and change it a little bit.
I use RM's Census fact and don't use RM's Residence fact. When RM's shared facts first came out, I didn't yet realize the degree of problems there were for data interchange with RM's shared facts. So I was not inhibited from trying RM's shared facts with RM's Census fact. For the purposes of the way they look in narrative reports, no two of my census facts look exactly the same. In order to achieve this same effect by sharing RM's Census fact, I had to do so much customization that sharing RM's census fact saved me no time at all. I therefore abandoned the sharing of RM's Census fact even before I came to realize the degree of problems there were for data interchange with RM's shared facts.
That being said, for some users some of the time, I think the kinds of facts that could effectively be copied without changing the newly pasted fact would be Census, Residence, Immigration, Emigration, and anything having to do with moving (e.g., moving a whole family from Tennessee to Missouri in 1854 would not usually be described as Immigration or Emigration - I think moving is a more apt term).