I appreciated this article very much and am in general agreement with much of it, but would like to make just a couple of points. One, while Ramakrishna did spend alot of is time in ascended or absorptive samadhis, there is a famous quote where he castigates Vivekananda for wanting to go into nirvikalpa samadhi for days on end by saying, "You fool ! There is a state much higher than that." It is thus possible that his frequent samadhis were more because of pre-existing tendencies rather than a belief in their absolute requirement. Near the end of his life Ramakrishna also said something like "I have now given away everything (ie., implying spiritual transmission) and am just a poor beggar." (However, this is paradoxical as he also lamented that "if this body could have lasted a little longer many more would find spiritual freedom"). Vivekananda near the end of his own life said, "more and more, the true greatness of life seems to be that of the worm doing its duty, silently and from moment to moment." So reference to the need for 'direct experience' by either of these two as the indication of adherence to a yogic neo-vedanta may not indicate a belief in the necessity of nirvikalpa samadhi in their cases.
An interesting comment in one of the books about Ramana Maharshi, who definitely did not teach the need for nirvikalpa samadhi for liberation, but rather the need for direct knowledge of the Self, has Ramana saying that Sankara died at age 32 because he worked too hard teaching and didn't spend enough time in nirvikalpa samadhi to "re-charge" himself! So for Ramana trance states would be a refreshment rather than a requirement for liberation or enlightenment.
Cowens does mention that for Sankara and his commentators, yoga and samadhi, while not producing enlightenment, may still have a preparatory and purificatory role for those whose minds are not ripe to make use of the more direct teaching of the vedanta. Such was the approach of Ramana Maharshi, who allowed his devotees to follow different practises, even though his method of choice was self-enquiry. An example of a modern sage, on the other hand, who underwent many such sadhanas leading to nirvikalpa samadhi, but who later rejected them all to advocate solely the path of jnana or knowledge was Shree Atmananda (Krishna Menon). He stated:
"The samadhi experience is that ‘I was happy.’ But when you understand, from a Karana-guru, that Happiness is your real nature, you come to realize that you are yourself the goal of samadhi. With this understanding, all hankering after samadhi disappears; though samadhi might still come upon you sometimes merely as a matter of course or samskara. But you will never again be attracted by the enjoyment of happiness in samadhi." - Notes on Spiritual Discourses, 928.