When I was writing the question, I remembered that someone had said (in a QOTD discussion) about his/her IMPLICIT_TRANSACTION option set to ON. And the result of the query had been different from that QOTD answer. This is why I decided to add the IMPLICIT_TRANSACTION statement in the script. And now I think it is another learning aspect of this QOTD: an implicit transaction may occur even with IMPLICIT_TRANSACTIONS = OFF, which was new to some respondents.

Thanks! And thank you for the excellent (as always) explanation! 🙂