Thanks to Kelly at Family History Fun: A light bulb moment!
People who know me know that I have a tendency to overthink things. I also love playing with data, so while I've known for a while that I need to harmonize the records I have on Ancestry.com with my regular family tree data (in Reunion), I haven't thought of an elegant way to do it. I started imagining scenarios of trying to merge data and people using various incarnations of GEDCOM files when I happened to see this post [Family History Fun: A light bulb moment!] today. This is a simple and probably workable solution for me (I think).
Most of the work I've done in Ancestry is on my direct ancestors (on either side), rather than on the many extensive lateral connections I have documented in Reunion. I'm thinking that if I methodically work my way through the generations I have a fighting chance of recording the Ancestry records in Reunion, saving copies as I go along. (I have little space for extensive paper files, so would prefer to go paperless when possible.)