I have seen tonnes evidence of this sort of `flailing' crows. But that is not surprising. Of all the difficult poses to reach, the crow is the most difficult to teach. Even in a headstand, which btw is also being taught in some Mumbai schools so sloppily or against the wall that I despair for yoga culture in this city, a teacher can protect one from a fall. This is true even of big, strapping practitioners. But in the crow the teacher cannot prevent a fall till form is reached and attention is given to the structure of the pose. It amazes me no end when I see students jump up and down (asking to fall and break their nose or chin or cut their lips), fget the features right one day (and lose it completely the next. Whyyy??!!), or even attempt it without any contact between thigh or arms (soooo moronic this one flips me completely). Yet, I want to teach them this pose so I am at it... Sometimes it takes some types a year to reach the basic crow. But I believe that the main philosophy of yoga is hidden in this pose: like fragrance in a flower which you must wait to blossom. I guess, like a bud too, not all are ready to bloom when they come to my class:)
Often for those who have never used their bodies with discipline, or the converse (which continues to surprise me no end) those who have gymmed excessively (this is an interesting part that when I teach yoga to those who have gymtrained, I realise that their limb coordination is is zero!!!) they find it hardest to reach. I am not joking. Something important seems to get lobotomized by that activity (gymming) that even I have indulged in, before yoga happened to me:)The other species that flails at the crow are the excessively philosophical ones who will talk (endlessly) to me of mind control but cannot seem to do so, on the mat (a famous local inst, and many teachers from there are great examples:).
To come to the point: the simplest trick in the crow is to focus on a spot in front of you (not under your nose, in which case you will have to fall!), not too high (beginners cannot lift their head against gravity too much, esp men); but about two feet ahead of you, on the ground (if lifting chin is tough) but ideally at a reasonable height (one-two feet off the ground). The point should not be big (like a chair), rather a pattern on the chair or a dot on it would be ideal.
This pose is one of learning to center yourself.
If you did not focus, you cannot reach it.
Strenght of mind.
Once you get the crow, you stop with the external focus and turn inward. That is when you actually are able to stay longer in the pose. That creates what is the white noise. It shuts out the mind. That is a beautiful place...
Focus requires you to dispense with the clutter and baggage in your mind. No wonder most people find this pose so difficult. We are all so weighed down by what we think, that comes in the way of our being. And living. Crow shows you up... That is why it is difficult... That is why most teachers don's wish to teach it...