Another vote to please clarify upsert behaviour for composite tuples.
We do get upsert behaviour when specifying the tuple attribute in the transaction (which goes against the statement in the documentation to never assert tuple attributes). Can we use this without fear that it will stop working in future?
Also, when using a :db.type/ref as part of the tuple, lookup refs are not resolved, meaning we have to query first to resolve all lookup refs. Would be great if lookup refs could work as per non-tuple ref attributes.