Tuples inserted and deleted by the same transaction

Shouldn't such tuples be considered dead right away, even if the inserting
transaction is still active?  That would allow cleaning them up even before
the transaction is done.

There is this code in HeapTupleSatisfiesVacuumHorizon:

        else if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmin(tuple)))
        {
            [...]
            /* inserted and then deleted by same xact */
            if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetUpdateXid(tuple)))
                return HEAPTUPLE_DELETE_IN_PROGRESS;

Why HEAPTUPLE_DELETE_IN_PROGRESS and not HEAPTUPLE_DEAD?

Yours,
Laurenz Albe