There are people collectively doing genealogy with Gramps as one of their tools… even though it wasn’t designed for collaborative work.
The Isotammi project is building Gramps tools for collective genealogy of Finland. Their Multimerge Gramplet is a popular addition.
I had a thought if you are doing a 2 person tag-team approach with your genealogy. There a discussion about an experimental TreeMerge addon. And there’s the Import Merge add-on tool.
Neither considers the Gramps ID as a reliable hint for merging. But what if you were able to work out a schema for helping the Merge process? Maybe the developers could be encouraged to leverage it as an option?
In combination with the datestamps, merged Gramps IDs and some sort of audit trail, a smarter merge might be possible.
Let’s say that you and your partner decide to loosely coordinate your work. You’ve started with a common base Tree in Gramps but each works independently. But you periodically harmonize the 2 Trees.
If you were to change your Gramps “ID tab” Preferences so that each researcher’s new object were in different ranges, then neither the Gramps ID nor the seeded handle are likely to overlap. In combination, they’d be very strong indicators.
By default, the F%04d range for Families allows for 10,000 families, ranging from F0000 to F9999. So instead, I might use a Fa%06d ID, ranging from Fa000000 to Fa999999. Meanwhile, my partner uses Fb%06d and the master merge Gramps uses F%06d (without a collaborator modifier).
Since ASCII has 52 single-keystroke non-symbol & non-numeric characters, you could support up to a team of 52 partners. (52 squared or 2,704 with a 2 character code.)
Any object with a Partner’s ID would not yet have been validated & merged into the Master tree. And, as part of a 2-person validation process, you should only merge your partner’s data into the master, not your own.
There’s already a loose form of coordinating the Place objects using the GeoCodes as IDs via the Place Cleanup addon. Any of the Place record IDs beginning with a “GEO” is a part of a master tree of Places.