the common interpretation of the jhānas as absorption-concentration attainments [is] incompatible with the teachings of the Pāli Nikāyas. […] one attains the jhānas, not by one-pointed concentration and absorption into a meditation object, but by releasing and letting go of the foothold of the unwholesome mind […] the entrance into the first jhāna is the actualization and embodiment of insight practice.

While I think that Arbel goes too far in saying that jhāna can only be an insight attainment, I think her thesis is broadly correct: the vipassana jhānas, while not at all like their fixed-concentration cousins, do exist, contain all the jhāna factors and, in fact, constitute sammā-samādhi.