According to such as the Gheraṇḍa Saṃhitā, Aśvinī Mudrā and Mūla Bandha
are seen as very different forms in terms of definition and application.
Regarding application, only Aśvinī Mudrā is focussed around
the repeated contraction of the anal sphincter muscles.
For example Mūla Bandha is described as something you always
take all the time whether sitting, talking, walking, or eating.
This would not be possible given T Krishnamacharya’s view of what is Mūla Bandha.
Equally T Krishnamacharya’s view of what is Aśvinī Mudrā and Mūla Bandha
differed both in terms of definition, technique, and application,
as well as regarding the student starting point prerequisites,
Vinyāsa Krama and links to other layers of our Yoga Sādhana.