This supercedes tickets 2984463 and 3309636; those tickets are closed, but much of the relevant discussion is on them.
The proposal is to create a class called att.sortable, which would provide @sortKey for elements which appear in groups or lists, but for which it is often difficult to derive a working sort key mechanically. Elements in this class would be:
item, bibl, biblStruct, biblFull, person personGrp, place, org, msDesc, idno, witness, relation, relationGrp, event, nym;
list, listBibl, listWit, listOrg, listEvent, listPerson, listPlace, listNym
The second set are included because they can be nested inside themselves.
Council has discussed this and is generally favourable.
The Council has discussed this