So much to cover…yikes.
It is clear from our studies that the musculature of the human body which is closer to the spine, closer to the nervous system, holds more powerful issues. Most of these muscles are smooth muscles or involuntary muscles (in terms of their contraction). The iliopsoas is a very significant muscle for so many reasons. Therefore it is not only important to address it must also be addressed with a heightened sense of care and mindfulness.
Just as not every student is ready for Pincha Mayurasana neither is every student ready for a floodgate of opening of deep emotions. Some may never be ready. Some may be ready immediately. Like all things yoga, teachers should error on the side of caution because a powerful release (be it Kundalini or emotions) in an unprepared student can be incredibly harmful and damaging.
The neurogenic tremor work looks interesting and I’d have to try it to give more feedback.
That having been said, there are a variety of reasons that muscles quiver, shake, or tremor. All of those trace back to the nervous system. My teacher has written a reply in Yoga Journal that says it far better than I could so I’ll link to that here.
In some views giving action to emotion only serves to continue the enslavement to them. There are some perspectives that suggest the deep grooves of our consciousness (samskara) are further etched by acting out these emotions. Instead it is oft suggested to merely observe them, thus serving as both the seer and the seen.
As we examine the Kleshas put forth in Patajali’s Sutras we see how attachment and aversion are BOTH obstacles. Therefore, in that construct, one would not become attached to emotional release nor would one shove it away and resist it. Many things come in the practice of yoga. And we take them all with grace no matter how the old brain or lower nature wants to view them.
As yoga teachers we must use care in clinging to a particular experience for students. As students we must use care in clinging to a particular experience for ourselves.