@waddink, please note that was a “thinking out loud” list and incomplete. Recently I have been uncovering more of these anomalies in biodiversity datasets, and they are hard to both test for and describe.
So your current plan is not to build corrected DESes (with documentation of the corrections), but instead to simply add on annotations with questions and corrections? How is that more simple than fixing or round-tripping records with a request to fix, so that the DES is fixed before it needs annotating?
Please also note that I am not suggesting fix/versioning/diffs as the “late-stage” DES model for DiSSCo, which is what both you and @sharif.islam seems to be thinking about. I am suggesting that DiSSCo can save everyone a lot of work and greatly improve DES quality if you do as many fixes as possible before you build the DES, which was the subject of this comment.