Rules and Errata

The Courtesan: When This Is the Hour: When you would encounter a non-story bane barrier, banish it instead, then summon and encounter a Task barrier.

Clearly this is not intended to cause an infinite loop, but as written it seems to. (You explore non-story bane barrier A. When you would encounter A, instead it is banished, then you summon and encounter Task barrier B. When you would encounter B, instead it is banished, then you summon and encounter Task barrier C, etc.)

Does this power (and others like it) need errata? Possible fixes could be to specify "non-Task" and/or "non-summoned" (or "from a location).
Or is there a general rule which prevents abilities from triggering multiple times?