A discussion on FB has drawn me into the TreeShare spaghetti of issues. It started with the complaint about "Residence (fam)" fact label on an Ancestry Member Tree created by a TreeShare Upload being changed to "Residence (family)" when the fact was updated to AMT for a change that had been made in RM. TreeShare no longer matches these otherwise identical facts so the fact on one side has to be added to the other and the remaining unmatched one deleted. Adding to RM may result in a custom individual fact type with "(family)" in the name - a source of confusion. Re-adding to AMT means deleting the renamed fact separately from both spouses. It gets more complicated because the TS Update to AMT only changes the value for the fact for one spouse - why not both?
I've pulled on a few spaghetti strings and tried to document my findings for other users to learn from, analyse, contribute to... and for RM developers to focus some corrective effort. They are Google Slides slideshows:
What little use I have made with TS has been for download so I had not noticed that a TS upload of a RM family-type fact produces a special fact on AMT. I understand that all AMT facts are supposed to be individual-type but uploads result in the other spouse's name being hyperlinked from the fact on the AMT Facts and Timeline pages of a person's Profile, just as is seen for (some) Marriage facts generated on the AMT from an Ancestry Source Hint. I haven't found a way to create such spousal hyperlinks through the AMT UI and, somehow, these cross-linked individual facts do get transformed through a download or a TS Add update from AMT to RM into RM family-type facts. So if TS Upload and Download can create these "family" versions on either side, why can't TS Update propagate changed values from one family fact in RM to both individual facts for the spouses on AMT and, likewise, in the opposite direction?