If I write on a sign then write on another sign and then edit the first sign, the text that I wrote on the second sign overwrites the text I originally wrote on the first when I go onto the first sign to edit it. It seems to me as though it is copy pasting whatever I have last written onto whatever I next write on. I don't know how to get a video off of my X-box so I can't show one but overall:
1. place sign #1 and write text on it (If I have written something on a sign previously it will just automatically have that on the sign)
2. place sign #2 and it has the same text that you wrote on sign #1
3. write new text on sign #2 and then edit sign #1 and the text that you wrote on sign #1 will be overwritten by the text you wrote on sign #2
This isn't a problem when placing signs but when editing them it deleting what was already there is not helpful.
The same applies for hanging signs but not for book and quill.